fix: use ubuntu-latest as ci runner (#52)

Author: UlisesGascon

.github/workflows/ci.yml

@@ -6,7 +6,7 @@ on:
 
 jobs:
   test:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         name:
@@ -222,4 +222,4 @@ jobs:
       uses: coverallsapp/github-action@master
       with:
         github-token: ${{ secrets.GITHUB_TOKEN }}
-        parallel-finished: true
+        parallel-finished: true