[FEA] Delete thread_safe_resource_adaptor: it is untested and likely no longer used

[harrism]

Is your feature request related to a problem? Please describe.
thread_safe_resource_adaptor used to be used for pool_memory_resource to make it thread safe, but now this and other MRs are internally thread safe.

Describe the solution you'd like
Delete this adaptor, as it is untested.

Describe alternatives you've considered
Write tests, which is more work.

[jrhemstad]

I'm not so sure. Talking with @abellina, we ran into a situation where they wanted to use limiting_resource_adapator, but it's not actually thread safe. The thread_safe_resource_adaptor would be a trivial solution.

[jrhemstad]

As far as testing goes, I think it's sufficient to just exercise that the allocation/deallocation work as expected. Trying to test thread safety is usually folly.

[harrism]

limiting_resource_adaptor is now thread-safe. #869

[github-actions]

This issue has been labeled inactive-30d due to no recent activity in the past 30 days. Please close this issue if no further response or action is needed. Otherwise, please respond with a comment indicating any updates or changes to the original issue and/or confirm this issue still needs to be addressed. This issue will be labeled inactive-90d if there is no activity in the next 60 days.

[harrism]

Since thread_safe_resource_adaptor is now tested, I'm closing this.