[GitHub] Highlight KLIB ABI dump as Kotlin on GitHub

github.com/github-linguist/linguist/blob/master/docs/overrides.md

See e.g. *.klib_abi.txt files in compiler/testData/klib/dump-abi

Author: ddolovov

.gitattributes

@@ -1,6 +1,7 @@
 **/testData/** linguist-vendored
 *Generated.java linguist-generated=true
 *.kt.txt linguist-language=Kotlin
+*.klib_abi.txt linguist-language=Kotlin
 * text=auto
 * eol=lf
 *.png binary