ci: disable TPU testing (#20942)

Author: Borda

.github/checkgroup.yml

@@ -71,7 +71,7 @@ subprojects:
   #    paths:
   #      # tpu CI availability is very limited, so we only require tpu tests
   #      # to pass when their configurations are modified
-  #      - ".github/workflows/tpu-tests.yml"
+  #      - ".github/workflows/tpu-tests.yml.disabled"
   #      - "tests/tests_pytorch/run_tpu_tests.sh"
   #    checks:
   #      - "test-on-tpus (pytorch, pjrt, v4-8)"
@@ -181,7 +181,7 @@ subprojects:
   #    paths:
   #      # tpu CI availability is very limited, so we only require tpu tests
   #      # to pass when their configurations are modified
-  #      - ".github/workflows/tpu-tests.yml"
+  #      - ".github/workflows/tpu-tests.yml.disabled"
   #      - "tests/tests_fabric/run_tpu_tests.sh"
   #    checks:
   #      - "test-on-tpus (pytorch, pjrt, v4-8)"