refactor(types): enable noImplicitAny in session-pool.ts

[josecervino]

Fixes #<issue_number_goes_here>

• Tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

Closed then opened again to make revisions simpler.

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[josecervino]

I signed it!

[googlebot]

CLAs look good, thanks!

[josecervino]

Most of the build fails have this error: Config validation failed!. Any idea what this means?

[callmehiphop]

@joecervino I think Kokoro just isn't feeling well today, haha.

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[callmehiphop]

@JustinBeckwith could you fight the cla robot for me?

[googlebot]

A Googler has manually verified that the CLAs look good.

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[googlebot]

So there's good news and bad news.

👍 The good news is that everyone that needs to sign a CLA (the pull request submitter and all commit authors) have done so. Everything is all good there.

😕 The bad news is that it appears that one or more commits were authored or co-authored by someone other than the pull request submitter. We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that here in the pull request.

Note to project maintainer: This is a terminal state, meaning the cla/google commit status will not change from this state. It's up to you to confirm consent of all the commit author(s), set the cla label to yes (if enabled on your project), and then merge this pull request when appropriate.

[googlebot]

A Googler has manually verified that the CLAs look good.

(Googler, please make sure the reason for overriding the CLA status is clearly documented in these comments.)

[JustinBeckwith]

I fought the bot, and the bot won

[callmehiphop]