[gtksourceview: 4/5] javascript.lang: Update supported level in documentation

[Christian Hergert <chergert src gnome org>]

commit 0e63574405bc66b88d5d9c6123897d90173c80f4
Author: Jeffery To <jeffery to gmail com>
Date:   Sat Jan 18 02:40:17 2020 +0800

    javascript.lang: Update supported level in documentation

 data/language-specs/javascript.lang | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)
---
diff --git a/data/language-specs/javascript.lang b/data/language-specs/javascript.lang
index 8f3fa3c9..170ccfec 100644
--- a/data/language-specs/javascript.lang
+++ b/data/language-specs/javascript.lang
@@ -131,16 +131,10 @@
 
          Current draft: https://tc39.es/ecma262/
 
-         Supported level: ES2019
-
-         Supported ES2020 proposals:
-         * String.prototype.matchAll
-         * import()
-         * BigInt
-         * Promise.allSettled
-         * globalThis
-         * Optional Chaining
-         * Nullish Coalescing operator
+         Supported level: ES2020
+
+         Supported ES2021 proposals:
+         * (none yet)
 
          Features from Annex B of the spec are not highlighted to
          discourage their use, except: