chore(advisor)!: Remove the GitHub defects advisor

This advisor does not seem to be used. Also, it depends on version 6 of
the Expedia GraphQL library which in turn depends on an old version of
the Ktor client that has known security vulnerability CVE-2023-45613.
So just remove this advisor completely.

Signed-off-by: Sebastian Schuberth <sebastian@doubleopen.org>

.gitattributes

@@ -27,7 +27,3 @@ utils/spdx/src/main/resources/licenses/*		linguist-detectable=false
 
 # Use Unix line endings for the expected control file of a Debian package.
 utils/common/src/test/assets/control-expected.txt	text eol=lf
-
-# Use Unix line endings for *.graphql files. This is mainly done to prevent that tests need to fiddle with
-# different platform-specific line endings.
-*.graphql	text eol=lf