Removed requirement on artist for search

src/musicbrainz.rs

@@ -106,11 +106,15 @@ impl MetadataProvider for MusicBrainzClient {
         artist: &str,
         album: &str,
     ) -> TagResult<Vec<ReleaseMatch>> {
-        let query = format!(
-            "artist:{} AND release:{}",
-            escape_lucene(artist),
-            escape_lucene(album)
-        );
+        let query = if artist.is_empty() {
+            format!("release:{}", escape_lucene(album))
+        } else {
+            format!(
+                "artist:{} AND release:{}",
+                escape_lucene(artist),
+                escape_lucene(album)
+            )
+        };
         let url = format!("{BASE_URL}/release/?query={}&fmt=json&limit=5", urlencoded(&query));
         let resp: MbReleaseSearchResponse = self.get_json(&url).await?;