ci: gate go/java/python tool caches to github-hosted runners (#12001)

Follow-up to #11985/#11986: setup-go/setup-java/setup-python steps
added or restructured since (e.g. by #11981's shared-artifact layout)
were missed. On self-hosted runners setup-go restores/saves a ~5GB
module cache archive per job — pure waste when the module cache is
already on local disk — and the restore blocks the job for minutes.

.github/workflows/kafka-tests.yml

@@ -151,7 +151,7 @@ jobs:
       uses: actions/setup-go@v7
       with:
         go-version: ^1.26
-        cache: true
+        cache: ${{ runner.environment == 'github-hosted' }}
         cache-dependency-path: |
           **/go.sum
       id: go
@@ -330,7 +330,7 @@ jobs:
       uses: actions/setup-go@v7
       with:
         go-version: ^1.26
-        cache: true
+        cache: ${{ runner.environment == 'github-hosted' }}
         cache-dependency-path: |
           **/go.sum
       id: go
@@ -492,7 +492,7 @@ jobs:
       uses: actions/setup-go@v7
       with:
         go-version: ^1.26
-        cache: true
+        cache: ${{ runner.environment == 'github-hosted' }}
         cache-dependency-path: |
           **/go.sum
       id: go
@@ -650,7 +650,7 @@ jobs:
       uses: actions/setup-go@v7
       with:
         go-version: ^1.26
-        cache: true
+        cache: ${{ runner.environment == 'github-hosted' }}
         cache-dependency-path: |
           **/go.sum
       id: go