[chore][receiver/apachespark] Wording and formatting changes in the README (open-telemetry#35335)

**Description:** <Describe what has changed.>
<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
Just some minor nits and suggestions to the README.

Author: crobert-1

receiver/apachesparkreceiver/README.md

@@ -12,11 +12,11 @@
 [contrib]: https://github.com/open-telemetry/opentelemetry-collector-releases/tree/main/distributions/otelcol-contrib
 <!-- end autogenerated section -->
 
-This receiver fetches metrics for an Apache Spark cluster through the Apache Spark REST API - specifically, the /metrics/json, /api/v1/applications/[app-id]/stages, /api/v1/applications/[app-id]/executors, and /api/v1/applications/[app-id]/jobs endpoints.
+This receiver fetches metrics for an Apache Spark cluster through the Apache Spark REST API - specifically, the `/metrics/json`, `/api/v1/applications/[app-id]/stages`, `/api/v1/applications/[app-id]/executors`, and `/api/v1/applications/[app-id]/jobs` endpoints.
 
 ## Purpose
 
-The purpose of this component is to allow monitoring of Apache Spark clusters and the applications running on them through the collection of performance metrics like memory utilization, CPU utilization, shuffle operations, garbage collection time, I/O operations, and more.
+The purpose of this component is to monitor Apache Spark clusters and the applications running on them through the collection of performance metrics like memory utilization, CPU utilization, shuffle operations, garbage collection time, I/O operations, and more.
 
 ## Prerequisites