workflows: Build and test with --locked

Make sure Cargo.lock is up-to-date.

Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>

Author: amboar

.github/workflows/main.yml

@@ -12,5 +12,5 @@ jobs:
           toolchain: stable
 
       - run: cargo clippy --all-targets -- -D warnings
-      - run: cargo build
-      - run: cargo test
+      - run: cargo build --locked
+      - run: cargo test --locked