tests: do not fail tests in a state with uncommitted .py file removal

The problem is that [hg locate] lists removed files too.
We use [hg files] instead because that does not list removed files.

tests/test-check-module-imports.t

@@ -1,45 +1,45
-#require test-repo hg10
+#require test-repo hg32
 
   $ . "$TESTDIR/helpers-testrepo.sh"
   $ import_checker="$TESTDIR"/../contrib/import-checker.py
 
   $ cd "$TESTDIR"/..
 
 There are a handful of cases here that require renaming a module so it
 doesn't overlap with a stdlib module name. There are also some cycles
 here that we should still endeavor to fix, and some cycles will be
 hidden by deduplication algorithm in the cycle detector, so fixing
 these may expose other cycles.
 
 Known-bad files are excluded by -X as some of them would produce unstable
 outputs, which should be fixed later.
 
-NOTE: the `hg locate` command here only works on files that are known to
+NOTE: the `hg files` command here only works on files that are known to
 Mercurial. If you add an import of a new file and haven't yet `hg add`ed it, you
 will likely receive warnings about a direct import.
 
-  $ testrepohg locate 'set:**.py or grep(r"^#!.*?python")' \
-  > 'tests/**.t' \
+  $ testrepohg files 'set:**.py or grep(r"^#!.*?python")' \
+  > 'glob:tests/**.t' \
   > -X hgweb.cgi \
   > -X setup.py \
   > -X contrib/automation/ \
   > -X contrib/debugshell.py \
   > -X contrib/hgweb.fcgi \
   > -X contrib/packaging/hg-docker \
   > -X contrib/packaging/hgpackaging/ \
   > -X contrib/packaging/inno/ \
   > -X contrib/phab-clean.py \
   > -X contrib/python-zstandard/ \
   > -X contrib/win32/hgwebdir_wsgi.py \
   > -X contrib/perf-utils/perf-revlog-write-plot.py \
   > -X doc/gendoc.py \
   > -X doc/hgmanpage.py \
   > -X i18n/posplit \
   > -X mercurial/thirdparty \
   > -X tests/hypothesishelpers.py \
   > -X tests/test-check-interfaces.py \
   > -X tests/test-demandimport.py \
   > -X tests/test-imports-checker.t \
   > -X tests/test-verify-repo-operations.py \
   > -X tests/test-extension.t \
   > | sed 's-\\-/-g' | "$PYTHON" "$import_checker" -