chore(mysql): handle timezone setting failure better

ibis/backends/mysql/__init__.py

@@ -4,6 +4,7 @@
 
 import atexit
 import contextlib
+import warnings
 from typing import Literal
 
 import sqlalchemy as sa
@@ -107,13 +108,18 @@ def do_connect(
     def begin(self):
         with super().begin() as bind:
             previous_timezone = bind.execute('SELECT @@session.time_zone').scalar()
-            bind.execute("SET @@session.time_zone = 'UTC'")
+            try:
+                bind.execute("SET @@session.time_zone = 'UTC'")
+            except Exception as e:  # noqa: BLE001
+                warnings.warn(f"Couldn't set MySQL timezone: {str(e)}")
 
             try:
                 yield bind
             finally:
-                query = "SET @@session.time_zone = '{}'"
-                bind.execute(query.format(previous_timezone))
+                try:
+                    bind.execute(f"SET @@session.time_zone = '{previous_timezone}'")
+                except Exception as e:  # noqa: BLE001
+                    warnings.warn(f"Couldn't reset MySQL timezone: {str(e)}")
 
     def _get_schema_using_query(self, query: str) -> sch.Schema:
         """Infer the schema of `query`."""