Fix bash checking scripts (#29)

Author: kubawerlos

.dev-tools/check_file_permissions.sh

@@ -2,9 +2,9 @@
 set -eu
 
 files_with_wrong_permissions=$(
+    cd $(git rev-parse --show-toplevel)
     git ls-files --stage . \
         ':!*.sh' \
-        ':!generate_readme\.php' \
     | grep '^100755 ' \
     | sort -fh
 )

.dev-tools/check_trailing_whitespaces.sh

@@ -24,6 +24,7 @@
 set -eu
 
 files_with_trailing_whitespaces=$(
+    cd $(git rev-parse --show-toplevel)
     git grep -EIn "\\s$" \
     | sort -fh
 )

.dev-tools/generate_readme.php

@@ -53,7 +53,7 @@ jobs:
 
     env:
       COMPOSER_PROCESS_TIMEOUT: 300
-      
+
     steps:
       - name: Checkout
         uses: actions/checkout@v2