Add `cache_key_enabled` option for ActiveSupport

[bouwkast]

Change log entry

Adds a new option for ActiveSupport to disable adding the cache_key as a Span Tag with the cache_key_enabled option.

What does this PR do?

• Adds cache_key_enabled to ActiveSupport (defaults to true)
• When cache_key_enabled is false it will no longer set the cache_key as a Span Tag

Motivation:

Customer feature request TODO GITHUB ISSUE LINK HERE

Additional Notes:

I have basic grasp on Ruby. An alternative here is to obfuscate/quantize cache_key values when we add them, the issue here is I'm not entirely sure what these values would look like and if they'd be valuable if they were obfuscated/quantized.

How to test the change?

On Windows can't install Ruby :( Can't get WSL to work after Windows Update Can't find tests for ActiveSupport that assert on tags Help

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