Firefox 138 supports dynamic import features (#26813)

Author: rviscomi

javascript/grammar.json

@@ -919,8 +919,7 @@
               },
               "edge": "mirror",
               "firefox": {
-                "version_added": false,
-                "impl_url": "https://bugzil.la/1736059"
+                "version_added": "138"
               },
               "firefox_android": "mirror",
               "ie": {

javascript/operators/import.json

@@ -116,8 +116,7 @@
               },
               "edge": "mirror",
               "firefox": {
-                "version_added": false,
-                "impl_url": "https://bugzil.la/1736059"
+                "version_added": "138"
               },
               "firefox_android": "mirror",
               "ie": {