Revert to 'str.format' for most URLs

In cases where the values being filled in did not intuitively describe
what they represented as URL components, it became difficult to figure
out the structure of the URL.

See: <beetbox#5337 (comment)>

beetsplug/beatport.py

@@ -229,8 +229,8 @@ def __init__(self, data):
         if "category" in data:
             self.category = data["category"]
         if "slug" in data:
-            self.url = (
-                f"https://beatport.com/release/{data['slug']}/{data['id']}"
+            self.url = "https://beatport.com/release/{}/{}".format(
+                data["slug"], data["id"]
             )
         self.genre = data.get("genre")
 
@@ -257,7 +257,9 @@ def __init__(self, data):
             except ValueError:
                 pass
         if "slug" in data:
-            self.url = f"https://beatport.com/track/{data['slug']}/{data['id']}"
+            self.url = "https://beatport.com/track/{}/{}".format(
+                data["slug"], data["id"]
+            )
         self.track_number = data.get("trackNumber")
         self.bpm = data.get("bpm")
         self.initial_key = str((data.get("key") or {}).get("shortName"))

beetsplug/plexupdate.py

@@ -22,7 +22,9 @@ def get_music_section(
 ):
     """Getting the section key for the music library in Plex."""
     api_endpoint = append_token("library/sections", token)
-    url = urljoin(f"{get_protocol(secure)}://{host}:{port}", api_endpoint)
+    url = urljoin(
+        "{}://{}:{}".format(get_protocol(secure), host, port), api_endpoint
+    )
 
     # Sends request.
     r = requests.get(
@@ -52,7 +54,9 @@ def update_plex(host, port, token, library_name, secure, ignore_cert_errors):
     )
     api_endpoint = f"library/sections/{section_key}/refresh"
     api_endpoint = append_token(api_endpoint, token)
-    url = urljoin(f"{get_protocol(secure)}://{host}:{port}", api_endpoint)
+    url = urljoin(
+        "{}://{}:{}".format(get_protocol(secure), host, port), api_endpoint
+    )
 
     # Sends request and returns requests object.
     r = requests.get(

test/plugins/test_art.py

@@ -82,11 +82,8 @@ class CAAHelper:
     MBID_RELEASE = "rid"
     MBID_GROUP = "rgid"
 
-    RELEASE_URL = f"coverartarchive.org/release/{MBID_RELEASE}"
-    GROUP_URL = f"coverartarchive.org/release-group/{MBID_GROUP}"
-
-    RELEASE_URL = "https://" + RELEASE_URL
-    GROUP_URL = "https://" + GROUP_URL
+    RELEASE_URL = f"https://coverartarchive.org/release/{MBID_RELEASE}"
+    GROUP_URL = f"https://coverartarchive.org/release-group/{MBID_GROUP}"
 
     RESPONSE_RELEASE = """{
     "images": [

test/plugins/test_ipfs.py

@@ -48,7 +48,7 @@ def test_stored_hashes(self):
                     ipfs_item = os.path.basename(want_item.path).decode(
                         _fsencoding(),
                     )
-                    want_path = f"/ipfs/{test_album.ipfs}/{ipfs_item}"
+                    want_path = "/ipfs/{}/{}".format(test_album.ipfs, ipfs_item)
                     want_path = bytestring_path(want_path)
                     self.assertEqual(check_item.path, want_path)
                     self.assertEqual(