Bugfix for enumer in go 1.22

[Groxx]

Enumer is currently crashing if make go-generate is run with Go 1.22: alvaroloes/enumer#71
Temporal helpfully found an easy fix: temporalio/sdk-go#1382
For the underlying cause: golang/go#62167
So I've mimicked that by just doing a go get golang.org/x/tools@latest in the tools-module.

And now make clean -> GOTOOLCHAIN=[go1.20.1 or go1.22.1] make go-generate both work correctly.
(you need Go 1.21 or newer to use GOTOOLCHAIN. highly recommended!)

Since this only affects build-time tools and doesn't change any generated code, it seems trivially safe, but I have not checked what all has changed in golang.org/x/tools across these versions.

[coveralls]

Pull Request Test Coverage Report for Build 018eed9e-f746-431a-a6f0-02d7f0cd49d2

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 71 unchanged lines in 16 files lost coverage.
• Overall coverage decreased (-0.02%) to 67.393%

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Files with Coverage Reduction	New Missed Lines	%
common/persistence/sql/sqlplugin/postgres/task.go	2	73.4%
common/task/parallel_task_processor.go	2	93.06%
common/persistence/sql/sqlplugin/postgres/db.go	2	80.0%
service/history/handler/handler.go	2	52.41%
common/task/fifo_task_scheduler.go	2	85.57%
service/matching/db.go	2	73.23%
common/util.go	2	91.78%
common/membership/hashring.go	2	84.69%
service/history/task/fetcher.go	2	85.05%
common/log/tag/tags.go	3	50.46%

Totals
Change from base Build 018eed95-97d4-41ce-9aad-b2b0609ba7ad:	-0.02%
Covered Lines:	98642
Relevant Lines:	146368

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💛 - Coveralls