Remove duplicate call to cache.get_path. NFC (emscripten-core#23655)

tools/link.py

@@ -233,11 +233,11 @@ def build_symbol_list(filename):
   # We need to use a separate lock here for symbol lists because, unlike with system libraries,
   # it's normally for these file to get pruned as part of normal operation.  This means that it
   # can be deleted between the `cache.get()` then the `read_file`.
-  with filelock.FileLock(cache.get_path(cache.get_path('symbol_lists.lock'))):
+  with filelock.FileLock(cache.get_path('symbol_lists.lock')):
     filename = cache.get(f'symbol_lists/{content_hash}.json', build_symbol_list)
     library_syms = json.loads(read_file(filename))
 
-    # Limit of the overall size of the cache to 100 files.
+    # Limit of the overall size of the cache.
     # This code will get test coverage since a full test run of `other` or `core`
     # generates ~1000 unique symbol lists.
     cache_limit = 500