minor #4712 Update .gitattributes to exclude phpstan configs (williamdes)

This PR was merged into the 3.x branch.

Discussion
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Update .gitattributes to exclude phpstan configs

They where added in #4458

Versions >= 3.16.0 have the not needed files

Commits
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2e0c874 Update .gitattributes to exclude phpstan configs

Author: fabpot

.gitattributes

@@ -8,3 +8,5 @@
 /.gitignore export-ignore
 /.php-cs-fixer.dist.php export-ignore
 /phpunit.xml.dist export-ignore
+/phpstan.neon.dist export-ignore
+/phpstan-baseline.neon export-ignore