schema_registry: subject_versions_has_any_of inc_del

Add support to `store::subject_versions_has_any_of` for including
deleted subject versions.

src/v/pandaproxy/schema_registry/sharded_store.cc

@@ -394,7 +394,7 @@ ss::future<bool> sharded_store::is_referenced(subject sub, schema_version ver) {
     // Find whether any subject version reference any of the schema
     co_return co_await _store.map_reduce0(
       [refs{std::move(references)}](store& s) {
-          return s.subject_versions_has_any_of(refs);
+          return s.subject_versions_has_any_of(refs, include_deleted::no);
       },
       false,
       std::logical_or<>{});

src/v/pandaproxy/schema_registry/store.h

@@ -431,11 +431,13 @@ class store {
         return has_ids;
     }
 
-    bool subject_versions_has_any_of(const schema_id_set& ids) {
-        return absl::c_any_of(_subjects, [&ids](const auto& s) {
-            return absl::c_any_of(s.second.versions, [&ids, &s](const auto& v) {
-                return !s.second.deleted && ids.contains(v.id);
-            });
+    bool subject_versions_has_any_of(
+      const schema_id_set& ids, include_deleted inc_del) {
+        return absl::c_any_of(_subjects, [&ids, inc_del](const auto& s) {
+            return absl::c_any_of(
+              s.second.versions, [&ids, &s, inc_del](const auto& v) {
+                  return (inc_del || !s.second.deleted) && ids.contains(v.id);
+              });
         });
     }