Pin version of parking_lot when running on MSRV

Author: WorksButNotTested

.github/workflows/main.yml

@@ -57,6 +57,8 @@ jobs:
         cargo update --package=flate2 --precise=1.0.35
         cargo update --package=textwrap --precise=0.16.1
         cargo update --package=once_cell --precise=1.20.3
+        cargo update --package=parking_lot --precise=0.12.3
+        cargo update --package=parking_lot_core --precise=0.9.10
 
     - run: >
         rustup target add
@@ -537,6 +539,8 @@ jobs:
         cargo update --package=flate2 --precise=1.0.35
         cargo update --package=textwrap --precise=0.16.1
         cargo update --package=once_cell --precise=1.20.3
+        cargo update --package=parking_lot --precise=0.12.3
+        cargo update --package=parking_lot_core --precise=0.9.10
 
     - run: |
         cargo test --verbose --features=all-apis --release --workspace -- --nocapture