refactor(@angular/cli): update Intellij/Webstorm settings

Intellij and Webstorm unfortunately don't the use the exact same
configuration system. For example, Intellij treats every project as
`JAVA_MODULE` but Webstorm doesn't recognize the `JAVA_MODULE`.
Therefore, I think that the modules.xml and iml should be left
out from version control.

refs #16152

Author: ahasall

.gitignore

@@ -9,6 +9,8 @@ jsconfig.json
 
 # Intellij IDEA/WebStorm
 # https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+.idea/**/*.iml
+.idea/**/modules.xml
 .idea/**/workspace.xml
 .idea/**/tasks.xml
 .idea/**/usage.statistics.xml