build: upgrade to @angular/language-service 9.0.0-next.15

Author: Keen Yee Liau

server/package.json

@@ -8,7 +8,7 @@
     "node": ">=10.9.0 <13.0.0"
   },
   "dependencies": {
-    "@angular/language-service": "^9.0.0-next.14",
+    "@angular/language-service": "^9.0.0-next.15",
     "vscode-languageserver": "~5.2.1",
     "vscode-uri": "^2.0.3"
   }

server/yarn.lock

@@ -2,10 +2,10 @@
 # yarn lockfile v1
 
 
-"@angular/language-service@^9.0.0-next.14":
-  version "9.0.0-next.14"
-  resolved "https://registry.yarnpkg.com/@angular/language-service/-/language-service-9.0.0-next.14.tgz#8260e71e30d88ed792929668816f3c7e8d3071f8"
-  integrity sha512-gz1h9SuytzZd1WfqzXLLu8BWqbVb1ccc4HOFiyUv5gcW77yK5r0JZlJ5NOTEnBXGkEjhUuyrUEc477fUPueIoQ==
+"@angular/language-service@^9.0.0-next.15":
+  version "9.0.0-next.15"
+  resolved "https://registry.yarnpkg.com/@angular/language-service/-/language-service-9.0.0-next.15.tgz#8d5c69bb520906ba3dbd1e843a9dc396b4832729"
+  integrity sha512-ASoJnpVF6mgWfylGhpMu4+iPr8BHHwhSqWYuK2IZ8A4bvp/vMQmKwBq2Z36xvErb3tU1HQLxL1AUyhFn7EHEBw==
 
 vscode-jsonrpc@^4.0.0:
   version "4.0.0"