fix: enforce LF line endings for shell scripts via .gitattributes

Unity Cloud Build Windows builds fail because shell scripts get checked
out with CRLF line endings on Windows, but execute on Unix-based build
agents. Adding `*.sh text eol=lf` ensures Git always uses LF for .sh
files regardless of platform.

Closes #9649

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: decentraland-bot

.gitattributes

@@ -16,6 +16,14 @@ Explorer/Assets/StreamingAssets/AssetBundles/**/*.meta -filter=lfs -diff=lfs -me
 *.dll filter=lfs diff=lfs merge=lfs -text
 
 
+##############################################################################
+# shell scripts — force LF so they run correctly on Unix-based build agents
+# even when checked out on Windows
+#
+##############################################################################
+*.sh text eol=lf
+
+
 ##############################################################################
 # unity specifics
 #