[CI] Install apt dependencies when running "pyright: Run test cases" (#13976)

tests/get_external_apt_dependencies.py

@@ -0,0 +1,20 @@
+#!/usr/bin/env python3
+
+import itertools
+import os
+import sys
+
+from ts_utils.metadata import read_metadata
+from ts_utils.paths import STUBS_PATH
+
+if __name__ == "__main__":
+    distributions = sys.argv[1:]
+    if not distributions:
+        distributions = os.listdir(STUBS_PATH)
+    dependencies = set(
+        itertools.chain.from_iterable(
+            read_metadata(distribution).stubtest_settings.apt_dependencies for distribution in distributions
+        )
+    )
+    for dependency in sorted(dependencies):
+        print(dependency)