Bug 1564972 [wpt PR 17681] - Support .mjs as a javascript suffix, a=testonly

Automatic update from web-platform-tests
Support .mjs as a javascript suffix
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wpt-commits: e1c9ae5f429295816c383fa25ad60097b8808235
wpt-pr: 17681

testing/web-platform/tests/tools/wptserve/wptserve/constants.py

@@ -20,7 +20,7 @@ content_types = utils.invert_dict({
     "text/css": ["css"],
     "text/event-stream": ["event_stream"],
     "text/html": ["htm", "html"],
-    "text/javascript": ["js"],
+    "text/javascript": ["js", "mjs"],
     "text/plain": ["txt", "md"],
     "text/vtt": ["vtt"],
     "video/mp4": ["mp4", "m4v"],