chore: add *.tgz pattern to .gitignore

Add **/*.tgz to .gitignore to prevent accidental commits of package
tarballs during testing. This standardizes the pattern across all
Socket repositories.

Author: jdalton

.gitignore

@@ -24,6 +24,7 @@ Thumbs.db
 .#*
 **/.cache
 **/node_modules
+**/*.tgz
 **/*.tmp
 **/*.tsbuildinfo
 /dist