added await keyword to completions and added test (#27912)

Author: fortythreesam

src/services/completions.ts

@@ -2150,7 +2150,7 @@ namespace ts.Completions {
                 case KeywordCompletionFilters.None:
                     return false;
                 case KeywordCompletionFilters.All:
-                    return kind === SyntaxKind.AsyncKeyword || !isContextualKeyword(kind) && !isClassMemberCompletionKeyword(kind) || kind === SyntaxKind.DeclareKeyword || kind === SyntaxKind.ModuleKeyword
+                    return kind === SyntaxKind.AsyncKeyword || SyntaxKind.AwaitKeyword || !isContextualKeyword(kind) && !isClassMemberCompletionKeyword(kind) || kind === SyntaxKind.DeclareKeyword || kind === SyntaxKind.ModuleKeyword
                         || isTypeKeyword(kind) && kind !== SyntaxKind.UndefinedKeyword;
                 case KeywordCompletionFilters.ClassElementKeywords:
                     return isClassMemberCompletionKeyword(kind);

tests/cases/fourslash/completionAwaitKeyword.ts

@@ -0,0 +1,4 @@
+//// /**/
+
+goTo.marker("")
+verify.completionListContains("await");