meson: Bump requirement to 1.1

WARNING: Project specifies a minimum meson_version '>= 0.60' but uses features which were added in newer versions:
* 1.1.0: {'feature_option.enable_if()'}

Caused by !1363 (merged)

.gitlab-ci.yml

@@ -156,11 +156,11 @@ meson static:
   extends: .meson
   needs: [ "trigger" ]
   script:
-    - meson build --default-library=static --prefix=$(pwd)/install -Dsodium-source=built-in --fatal-meson-warnings
+    - meson build --default-library=static --prefix=$(pwd)/install -Dsodium-source=built-in
     - ninja -C build install
     - ./ci/generate-static-test.py test-static-link-all
     - cd test-static-link-all
-    - PKG_CONFIG_PATH=$PKG_CONFIG_PATH:$(pwd)/../install/lib/x86_64-linux-gnu/pkgconfig meson build --fatal-meson-warnings
+    - PKG_CONFIG_PATH=$PKG_CONFIG_PATH:$(pwd)/../install/lib/x86_64-linux-gnu/pkgconfig meson build
     - ninja -C build
     - ./build/test-gst-static
   artifacts: