test_open_file_cache_invalidate: Add delay to hopefully improve robustness

test/solidlsp/test_ls_common.py

@@ -1,4 +1,5 @@
 import os
+import time
 
 import pytest
 
@@ -33,6 +34,9 @@ class TestLanguageServerCommonFunctionality:
                 with open(file_path, "w") as f:
                     f.write(test_string2)
 
+                # give the file system some time to update the modified time
+                time.sleep(3)
+
                 # check that the file buffer has been invalidated and reloaded
                 assert fb.contents == test_string2