v2/internal/proxy: many tests failed

Many tests failed at the same time in this package.

* I will close this issue when there are no more failures in this package _and_
there is at least one pass.
* No new issues will be filed for this package until this issue is closed.
* If there are already issues for individual test cases, I will close them when
the corresponding test passes. You can close them earlier, if you prefer, and
I won't reopen them while this issue is still open.

Here are the tests that failed:
* TestFUSEREADME (#2641)
* TestFUSEDialInstance/connecting_creates_intermediate_temp_directories (#2642)
* TestFUSEAcceptErrorReturnedFromServe (#2643)
* TestFUSEReadDir (#2644)
* TestLookupIgnoresContext (#2645)
* TestFUSEErrors (#2646)
* TestFUSEWithBadInstanceName (#2647)
* TestFUSECheckConnections (#2648)
* TestFUSEClose (#2649)
* TestClientInitialization/with_incrementing_automatic_port_selection (#2550)

-----
commit: e0935a5219c622bc7e69fd9fa0fe17147dca9548
buildURL: https://github.com/GoogleCloudPlatform/cloud-sql-proxy/actions/runs/31143184851
status: failed

Start by running the tests in v2/internal/proxy for commit e0935a5219c622bc7e69fd9fa0fe17147dca9548, beginning with the failures listed in the issue and the linked individual issues. Done means there are no remaining failures in this package and at least one test passes.

Written by the indexing model from the issue text.