IMDb import: fix progress reporting

Because we calculated the percentage based on the number of lines we
need to yield once per line, otherwise the count is off.

unwind/imdb_import.py

@@ -177,13 +177,14 @@ def read_ratings_as_mapping(path: Path):
     return {r[0]: (round(100 * (float(r[1]) - 1) / 9), int(r[2])) for r in rows}
 
 
-def read_basics(path: Path):
+def read_basics(path: Path) -> Generator[Movie | None, None, None]:
     mtime = gz_mtime(path)
     rows = read_imdb_tsv(path, BasicRow)
 
     for row in rows:
         if row.startYear is None:
             log.debug("Skipping movie, missing year: %s", row)
+            yield None
             continue
 
         m = row.as_movie()
@@ -210,6 +211,9 @@ async def import_from_file(*, basics_path: Path, ratings_path: Path):
             log.info("⏳ Imported %s%%", round(perc, 1))
             perc_next_report += perc_step
 
+        if m is None:
+            continue
+
         if m.media_type not in {
             "Movie",
             "Short",
@@ -234,6 +238,7 @@ async def import_from_file(*, basics_path: Path, ratings_path: Path):
         await add_or_update_many_movies(chunk)
         chunk = []
 
+    log.info("👍 Imported 100%")
     await db.set_import_progress(100)