[README] links caption (#11893)

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Ex. Adding a feature - Explain what this achieves.-->
#### Description
Provide caption of a link in README
<!-- Issue number if applicable -->
#### Link to tracking issue
Fixes #

<!--Describe what testing was performed and which tests were added.-->
#### Testing

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#### Documentation

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README.md

@@ -36,7 +36,7 @@
       •  
     <a href="https://opentelemetry.io/docs/collector/configuration/">Configuration</a>
     &nbsp;&nbsp;&bull;&nbsp;&nbsp;
-    <a href="https://opentelemetry.io/docs/collector/internal-telemetry/#use-internal-telemetry-to-monitor-the-collector</a>
+    <a href="https://opentelemetry.io/docs/collector/internal-telemetry/#use-internal-telemetry-to-monitor-the-collector">Monitoring</a>
     &nbsp;&nbsp;&bull;&nbsp;&nbsp;
     <a href="docs/security-best-practices.md">Security</a>
     &nbsp;&nbsp;&bull;&nbsp;&nbsp;

docs/security-best-practices.md

@@ -82,7 +82,7 @@ sensitive and non-sensitive data as the Collector MUST support environment
 variable expansion.
 
 > For more information on environment variable expansion, see
-> [this](https://opentelemetry.io/docs/collector/configuration/#configuration-environment-variables)
+> [this](https://opentelemetry.io/docs/collector/configuration/#environment-variables)
 > documentation.
 
 When defining Go structs for configuration data that may contain sensitive information, use the `configopaque` package to define fields with the `configopaque.String` type. This ensures that the data is masked when serialized to prevent accidental exposure.