add step for deno check

Author: unixfox

.github/workflows/deno-check.yaml

@@ -19,6 +19,9 @@ jobs:
 
       - name: Verify formatting
         run: deno fmt --check src/**
+
+      - name: Verify typing
+        run: deno check src/**
 
       - name: Run linter
         run: deno lint