chore(docs): stop readthedocs spellcheck [backport 3.19]

[dd-octo-sts]

Backport bb0792b from #15679 to 3.19.

Description

ReadTheDocs environments don't set READTHEDOCS=True as expected. Update the build script to accept READTHEDOCS=1 (as set in .readthedocs.yml) and normalize the value (case-insensitive, strip whitespace) to match both "true" and "1".

Testing

Tested with "True", "TRUE", "true", "1", and " true ", all correctly match. Empty, "False", and "0" correctly do not match.

Additional Notes

Failing job: https://app.readthedocs.org/projects/ddtrace/builds/30721096/

[github-actions]

CODEOWNERS have been resolved as:

.readthedocs.yml                                                        @DataDog/python-guild @DataDog/apm-core-python
scripts/docs/build.sh                                                   @DataDog/python-guild

[emmettbutler]

I don't think this needs to be backported. Please reopen if you disagree.

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and base.

Summary

The average import time from this PR is: 251 ± 8 ms.

The average import time from base is: 244 ± 1 ms.

The import time difference between this PR and base is: 6.4 ± 0.3 ms.

Import time breakdown

The following import paths have grown:

ddtrace.auto 3.276 ms (1.31%)

ddtrace 2.021 ms (0.81%)

ddtrace._logger 1.267 ms (0.51%)

ddtrace.internal.telemetry 1.267 ms (0.51%)

ddtrace.internal.telemetry.writer 0.592 ms (0.24%)

ddtrace.settings._telemetry 0.194 ms (0.08%)

ddtrace.settings._inferred_base_service 0.022 ms (0.01%)

http.client 0.111 ms (0.04%)

ssl 0.072 ms (0.03%)

_ssl 0.072 ms (0.03%)

ddtrace.internal.endpoints 0.076 ms (0.03%)

ddtrace.internal.packages 0.052 ms (0.02%)

_sysconfigdata__linux_x86_64-linux-gnu 0.052 ms (0.02%)

ddtrace.internal.periodic 0.051 ms (0.02%)

ddtrace.internal._threads 0.051 ms (0.02%)

ddtrace.internal.encoding 0.048 ms (0.02%)

ddtrace.internal._encoding 0.048 ms (0.02%)

ddtrace.internal.telemetry.metrics_namespaces 0.042 ms (0.02%)

ddtrace.internal.telemetry.data 0.018 ms (0.01%)

ddtrace.settings._agent 0.338 ms (0.13%)

ddtrace.settings 0.232 ms (0.09%)

ddtrace.vendor.debtcollector 0.232 ms (0.09%)

ddtrace.vendor 0.190 ms (0.08%)

ddtrace.internal.module 0.190 ms (0.08%)

ddtrace.internal.wrapping.context 0.190 ms (0.08%)

ddtrace.internal.wrapping 0.190 ms (0.08%)

bytecode 0.190 ms (0.08%)

bytecode.bytecode 0.190 ms (0.08%)

bytecode.flags 0.190 ms (0.08%)

bytecode.instr 0.190 ms (0.08%)

ddtrace.vendor.debtcollector.moves 0.042 ms (0.02%)

ddtrace.settings._core 0.105 ms (0.04%)

ddtrace.internal.native 0.105 ms (0.04%)

ddtrace.internal.native._native 0.105 ms (0.04%)

ddtrace.internal.utils.formats 0.232 ms (0.09%)

ddtrace.internal.compat 0.232 ms (0.09%)

wrapt 0.232 ms (0.09%)

wrapt.importer 0.207 ms (0.08%)

importlib.metadata 0.207 ms (0.08%)

zipfile 0.032 ms (0.01%)

shutil 0.032 ms (0.01%)

importlib.metadata._adapters 0.026 ms (0.01%)

email.message 0.026 ms (0.01%)

email.utils 0.026 ms (0.01%)

socket 0.026 ms (0.01%)

_socket 0.026 ms (0.01%)

wrapt.__wrapt__ 0.025 ms (0.01%)

wrapt._wrappers 0.025 ms (0.01%)

ddtrace.settings._otel_remapper 0.061 ms (0.02%)

ddtrace.trace 0.754 ms (0.30%)

ddtrace._trace.filters 0.438 ms (0.17%)

ddtrace._trace.processor 0.438 ms (0.17%)

ddtrace.internal.writer 0.285 ms (0.11%)

ddtrace.internal.writer.writer 0.285 ms (0.11%)

ddtrace.settings.asm 0.226 ms (0.09%)

ddtrace.appsec._constants 0.175 ms (0.07%)

ddtrace.internal.dogstatsd 0.059 ms (0.02%)

ddtrace.vendor.dogstatsd 0.059 ms (0.02%)

ddtrace.vendor.dogstatsd.base 0.059 ms (0.02%)

ddtrace._trace.sampler 0.152 ms (0.06%)

ddtrace._trace.span 0.152 ms (0.06%)

ddtrace._trace._span_pointer 0.056 ms (0.02%)

hashlib 0.056 ms (0.02%)

_hashlib 0.056 ms (0.02%)

ddtrace.internal.core 0.052 ms (0.02%)

ddtrace.internal.core.event_hub 0.052 ms (0.02%)

ddtrace._trace.tracer 0.071 ms (0.03%)

ddtrace.internal.debug 0.026 ms (0.01%)

ddtrace.bootstrap.sitecustomize 1.255 ms (0.50%)

ddtrace.bootstrap.preload 1.041 ms (0.42%)

multiprocessing 0.371 ms (0.15%)

multiprocessing.context 0.371 ms (0.15%)

multiprocessing.reduction 0.321 ms (0.13%)

pickle 0.297 ms (0.12%)

_compat_pickle 0.235 ms (0.09%)

multiprocessing.process 0.025 ms (0.01%)

ddtrace.settings.profiling 0.328 ms (0.13%)

ddtrace.vendor.psutil 0.205 ms (0.08%)

ddtrace.vendor.psutil._pslinux 0.133 ms (0.05%)

ddtrace.vendor.psutil._psutil_linux 0.029 ms (0.01%)

ddtrace.internal.datadog.profiling.ddup 0.059 ms (0.02%)

ddtrace.internal.datadog.profiling.ddup._ddup 0.059 ms (0.02%)

ddtrace.internal.symbol_db.remoteconfig 0.161 ms (0.06%)

ddtrace.internal.symbol_db.symbols 0.105 ms (0.04%)

ddtrace.internal.core.crashtracking 0.144 ms (0.06%)

multiprocessing.sharedctypes 0.036 ms (0.01%)

ctypes 0.036 ms (0.01%)

_ctypes 0.036 ms (0.01%)

ddtrace._trace.trace_handlers 0.187 ms (0.07%)

ddtrace._trace._inferred_proxy 0.111 ms (0.04%)

ddtrace.propagation.http 0.111 ms (0.04%)

ddtrace.internal._tagset 0.043 ms (0.02%)

ddtrace.bootstrap.cloning 0.027 ms (0.01%)

The following import paths have shrunk:

ddtrace.auto 1.104 ms (0.44%)

ddtrace 0.658 ms (0.26%)

ddtrace.internal._unpatched 0.025 ms (0.01%)

json 0.025 ms (0.01%)

json.decoder 0.025 ms (0.01%)

re 0.025 ms (0.01%)

enum 0.025 ms (0.01%)

types 0.025 ms (0.01%)

ddtrace.bootstrap.sitecustomize 0.446 ms (0.18%)

ddtrace.bootstrap.preload 0.446 ms (0.18%)

ddtrace.internal.remoteconfig.client 0.446 ms (0.18%)