tools: remove src dir from JS editorconfig rule

The src directory does not contain any JavaScript files, so there is no
need to match it.

PR-URL: https://github.com/nodejs/node/pull/19521
Reviewed-By: Shingo Inoue <leko.noor@gmail.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>

.editorconfig

@@ -9,7 +9,7 @@ insert_final_newline = true
 [vcbuild.bat]
 end_of_line = crlf
 
-[{lib,src,test}/**.js]
+[{lib,test}/**.js]
 indent_style = space
 indent_size = 2