Fixes WebStorm capitalization in comment

On line 1, WebStorm is capitalized the same way as the other IDE names.

Global/JetBrains.gitignore

@@ -1,4 +1,4 @@
-# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and WebStorm
 # Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
 
 # User-specific stuff: