Auto merge of #19304 - asajeffrey:test-perf-dash-dash-submit, r=jdm

Renamed mach test-perf -submit to --submit.

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The `-submit` option should be `--submit` (2 dashes, not one).

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because they are test infrastructure

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python/servo/testing_commands.py

@@ -175,7 +175,7 @@ class MachCommands(CommandBase):
              category='testing')
     @CommandArgument('--base', default=None,
                      help="the base URL for testcases")
-    @CommandArgument('-submit', '-a', default=False, action="store_true",
+    @CommandArgument('--submit', '-a', default=False, action="store_true",
                      help="submit the data to perfherder")
     def test_perf(self, base=None, submit=False):
         self.set_software_rendering_env(True)