add PHP8.0 to CI, update gitlabCi

.github/workflows/main.yml

@@ -14,17 +14,5 @@ jobs:
       - name: Validate composer.json and composer.lock
         run: composer validate
 
-      - name: Cache Composer packages
-        id: composer-cache
-        uses: actions/cache@v2
-        with:
-          path: vendor
-          key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
-          restore-keys: |
-            ${{ runner.os }}-php-
-      - name: Install dependencies
-        if: steps.composer-cache.outputs.cache-hit != 'true'
-        run: composer install --prefer-dist --no-progress --no-suggest
-
       - name: Run Tests And Lint
         run: composer test

.travis.yml

@@ -4,6 +4,7 @@ php:
   - 7.2
   - 7.3
   - 7.4
+  - 8.0
 
 before_script:
   - composer self-update