ci: skip setup-go cache on self-hosted runners (#11985)

* ci: skip setup-go cache on self-hosted runners

The module cache is already local on a persistent self-hosted runner;
archiving ~/go/pkg/mod into cache.tzst at every job's end is pure cost
and can stall (a ~4-minute zstdmt hang was observed on awscli-tests).
runner.environment gates the cache to GitHub-hosted runners only.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* ci: gate the remaining setup-go caches too

The first pass only covered go-version-file steps; go-version steps in
nine workflows (including awscli-tests' own file) kept uploading the
cache archive on self-hosted runners.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

---------

Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

.github/workflows/fuse-integration.yml

@@ -37,6 +37,7 @@ jobs:
       uses: actions/setup-go@v7
       with:
         go-version-file: 'go.mod'
+        cache: ${{ runner.environment == 'github-hosted' }}
 
     - name: Configure FUSE
       run: |