Remove SCAP File Upload Size Limit from database table

[CDellaGiusta]

What does this PR change?

As referred from issue https://github.com/SUSE/spacewalk/issues/26829 the database field scap_file_sizelimit from the table rhnOrgConfiguration should be removed since that is a "dead" field (not referenced, read, updated by anyone)

GUI diff

No difference.

• DONE

Documentation

• No documentation needed: only internal and user invisible changes
• DONE

Test coverage

• No tests: already covered
• DONE

Links

Issue(s): https://github.com/SUSE/spacewalk/issues/26829
Port(s): not backported to 4.3
https://github.com/SUSE/spacewalk/pull/27679

• DONE

Changelogs

• No changelog needed

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• Re-run test "schema_migration_test_pgsql"
• Re-run test "susemanager_unittests"
• Re-run test "javascript_lint"
• Re-run test "spacecmd_unittests"

[mcalmer]

Looks good, but before we merge this we need to check in which directory we need to put the schema migration file.