fix: revert "feat: Download Flux modules within runtime as part of Salsa query (#5324)"

[nathanielc]

This reverts commit cced93e. The commit broke nightlies.

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[jdstrand]

Fyi, this issue fixed the following in passing before an issue could be filed:

 - type: dependabot
   dependency: hyper
   detectedIn: libflux/Cargo.lock
   severity: medium
   advisory: https://github.com/advisories/GHSA-5h46-h7hh-c6x9
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/13
 - type: dependabot
   dependency: hyper
   detectedIn: libflux/Cargo.lock
   severity: low
   advisory: https://github.com/advisories/GHSA-f3pg-qwvg-p99c
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/14
 - type: dependabot
   dependency: tiny_http
   detectedIn: libflux/Cargo.lock
   severity: medium
   advisory: https://github.com/advisories/GHSA-7v2r-wxmg-mgvc
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/15
 - type: dependabot
   dependency: traitobject  
   detectedIn: libflux/Cargo.lock
   severity: critical
   advisory: https://github.com/advisories/GHSA-j79j-cx3h-g27h
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/16
 - type: dependabot
   dependency: hyper
   detectedIn: libflux/Cargo.lock
   severity: high
   advisory: https://github.com/advisories/GHSA-f67m-9j94-qv9j
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/17
 - type: dependabot
   dependency: traitobject
   detectedIn: libflux/Cargo.lock
   severity: critical
   advisory: https://github.com/advisories/GHSA-pp8r-vv2j-9j5v
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/17
 - type: dependabot
   dependency: traitobject
   detectedIn: libflux/Cargo.lock
   severity: critical
   advisory: https://github.com/advisories/GHSA-pp8r-vv2j-9j5v
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/18
 - type: dependabot
   dependency: typemap
   detectedIn: libflux/Cargo.lock
   severity: critical
   advisory: https://github.com/advisories/GHSA-vfv3-9w6v-23jp
   status: released
   url: https://github.com/influxdata/flux/security/dependabot/19

This was noted in https://github.com/influxdata/influx-security-tools-cve-data/blob/main/retired/CVE-2022-GH5342%23flux: "PR 5342 wasn't for this, but the regenerated Cargo.lock had all the fixes. Marking as 'medium' for now. The deps were removed and don't know the actual priority matches the upstream severity. Could investigate more fully, but since they're resolved, don't worry about it and treat it like a normal issue."