[chore] Skip Supervisor log file test on Windows (#35591)

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#### Description

Follow up to
#35588.

This skips the test on Windows. The logic should be similar on other
operating systems, so it's not a significant loss to skip it. The issue
arises because Zap does not close log files itself and provides no
handles to close them, so we would need to find a clever way to close
the file or would need to simply not clean it up after the test
executes.

cmd/opampsupervisor/e2e_test.go

@@ -1363,6 +1363,10 @@ type LogEntry struct {
 }
 
 func TestSupervisorInfoLoggingLevel(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("Zap does not close the log file and Windows disallows removing files that are still opened.")
+	}
+
 	storageDir := t.TempDir()
 	remoteCfgFilePath := filepath.Join(storageDir, "last_recv_remote_config.dat")