ci: simplify twister args

s/G/--integration (more clear)
s/--testsuite-root/-T (shorter, still clear)

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

Author: gmarull

.github/workflows/build.yml

@@ -32,7 +32,7 @@ jobs:
       - name: Twister Tests
         working-directory: example-application
         run: |
-          west twister -G --testsuite-root ./tests/
+          west twister -T tests --integration
 
       - name: Archive firmware
         uses: actions/upload-artifact@v3