refactor ci config

.gitlab-ci.yml

@@ -6,7 +6,7 @@ stages:
 before_script:
   - apt update && apt install -y pkg-config libssl-dev
 
-rust-latest:
+rust-latest: &build_and_test
   stage: build
   cache:
     key: shared-cache
@@ -17,16 +17,9 @@ rust-latest:
     - cargo test --verbose
 
 rust-nightly: &rust_nightly
-  stage: build
+  <<: *build-and-test
   image: rustlang/rust:nightly
   allow_failure: true
-  cache:
-    key: shared-cache
-    paths:
-      - target/
-  script:
-    - cargo build
-    - cargo test --verbose
 
 clippy:
   <<: *rust_nightly