Use - instead of _ in LESS file names as language code

Change-Id: Ifcd6d8f927a651d13e8a01ac3995210292551bc8

src/ResourceLoader/CiteCSSFileModule.php

@@ -27,7 +27,7 @@ class CiteCSSFileModule extends FileModule {
 		// Get the content language code, and all the fallbacks. The first that
 		// has a ext.cite.style.<lang code>.css file present will be used.
 		foreach ( [ $contLang->getCode(), ...$contLang->getFallbackLanguages() ] as $lang ) {
-			$langStyleFile = 'ext.cite.style.' . strtr( $lang, '-', '_' ) . '.less';
+			$langStyleFile = "ext.cite.style.$lang.less";
 			if ( file_exists( $this->getLocalPath( $langStyleFile ) ) ) {
 				$this->styles[] = $langStyleFile;
 				break;