Remove unnecessary files from Composer package

Author: s1lver

src/Instrumentation/Yii/.gitattributes

@@ -0,0 +1,9 @@
+* text=auto eol=lf
+
+/.phan              export-ignore
+/tests              export-ignore
+.gitattributes      export-ignore
+.php-cs-fixer.php   export-ignore
+phpstan.neon.dist   export-ignore
+phpunit.xml.dist    export-ignore
+psalm.xml.dist      export-ignore