[Fix] Include content URLs in rspamadm mime urls output

[Fix] Include content URLs in rspamadm mime urls output

Change get_urls(true) to get_urls_filtered() to include URLs
extracted from content (e.g., PDF attachments) in the output.

The get_urls() function excludes RSPAMD_URL_FLAG_CONTENT URLs
by default for backward compatibility, but get_urls_filtered()
with no arguments returns all URLs including content URLs.