Add documentation for the tools option in the various workflow files

[NlightNFotis]

Description

Documents the tools: input and its options for the various workflow files.

Companion PR to #2281

Fixes #1327

Merge / deployment checklist

• Confirm this change is backwards compatible with existing workflows.
• Confirm the readme has been updated if necessary.
• Confirm the changelog has been updated if necessary.

[henrymercer]

Thanks! I made a suggestion to make it clearer the recommended case of not passing this input to let the CodeQL Action choose which tools to use.

[aeisenberg]

This is an action used internally for testing only. Maybe better to change this to:

Suggested change

	The version of the CodeQL tools to use. This can be any of the following:
	The version of CodeQL passed to the `tools` input of the init action.

[aeisenberg]

Same comment as above.

[aeisenberg]

I think keeping this line and removing the # is useful. At some point, but not here, we should document exactly which places are checked.

[henrymercer]

The "check in several places" comment feels more about implementation under the hood than what the input actually means, and in fact applies even if you do specify an input. For instance, if you specify a URL we will try to extract the CodeQL version from the URL and use the toolcache if we can find a matching version. Overall, I'd prefer to remove this in favour of saying we'll use the recommended version if you don't specify an input, but I don't feel that strongly about it.

[henrymercer]

The "check in several places" comment feels more about implementation under the hood than what the input actually means, and in fact applies even if you do specify an input. For instance, if you specify a URL we will try to extract the CodeQL version from the URL and use the toolcache if we can find a matching version. Overall, I'd prefer to remove this in favour of saying we'll use the recommended version if you don't specify an input, but I don't feel that strongly about it.