Rename the dependency parser script back to a regular .py suffix. (pa…

…ntsbuild#17955)

We changed it as part of the attempts to deal with resource loading
challenges under pyoxidizer. But now that we're not pursuing that
path we can restore it.

src/python/pants/backend/python/dependency_inference/BUILD

@@ -1,11 +1,7 @@
 # Copyright 2020 Pants project contributors (see CONTRIBUTORS.md).
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
-python_sources(
-    dependencies=[
-        "./scripts:dependency_parser",
-    ],
-)
+python_sources()
 
 python_tests(
     name="tests",

src/python/pants/backend/python/dependency_inference/parse_python_dependencies.py

@@ -60,7 +60,7 @@ class ParserScript:
 
 @rule
 async def parser_script() -> ParserScript:
-    script = read_resource(__name__, "scripts/dependency_parser_py")
+    script = read_resource(__name__, "scripts/dependency_parser.py")
     assert script is not None
     return ParserScript(
         await Get(Digest, CreateDigest([FileContent("__parse_python_dependencies.py", script)]))

src/python/pants/backend/python/dependency_inference/scripts/BUILD

@@ -3,13 +3,11 @@
 
 resource(
     name="dependency_parser",
-    source="dependency_parser_py",
+    source="dependency_parser.py",
 )
 
-# Also expose scripts as python sources so they get formatted/linted/checked.
+# Also expose script as a python source so it gets formatted/linted/checked.
 python_source(
     name="dependency_parser_source",
-    source="dependency_parser_py",
-    # This is run with Python 2.7 and 3.5+, so we shouldn't be running pyupgrade.
-    # skip_pyupgrade=True,
+    source="dependency_parser.py",
 )