fix(tests): remove repository_url from proxy PURL qualifiers

Remove repository_url from the direct source qualifiers that are used to
establish whether a proxy_url should be expected in the PURL for a given
Component. From Hermeto's perspective, repository_url is taken directly
from the pip requirements file. A proxy_url could be configured to point
to an alternative registry, which is unknowable for Hermeto.

Signed-off-by: Taylor Madore <tmadore@redhat.com>

Author: taylormadore

tests/integration/proxy.py

@@ -44,7 +44,7 @@
     f"{APP_NAME}_YARN__PROXY_PASSWORD": _DEFAULT_PROXY_PASSWORD,
 }
 
-_DIRECT_SOURCE_QUALIFIERS = frozenset({"vcs_url", "download_url", "repository_url"})
+_DIRECT_SOURCE_QUALIFIERS = frozenset({"vcs_url", "download_url"})
 
 
 def is_local_nexus_enabled() -> bool: