chore(gh): update release workflow (#3967)

Updated the release workflow to read the Go version from `go.mod` instead of a hardcoded '1.25'. This makes the CI use the module-declared Go version to avoid version drift and improve maintainability.

Signed-off-by: Ryan Johnson <ryan.johnson@broadcom.com>

Author: tenthirtyam

.github/workflows/govmomi-release.yaml

@@ -65,7 +65,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@7a3fe6cf4cb3a834922a1244abfce67bcef6a0c5 # v6.2.0
         with:
-          go-version: '1.25'
+          go-version-file: go.mod
       - name: Update version.go
         run: |
           # strip semantic v