CI: Remove build stage

`cargo test` rebuilds all of it anyway.

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

.gitlab-ci.yml

@@ -1,6 +1,5 @@
 stages:
   - lint
-  - build
   - test
 
 variables:
@@ -14,11 +13,6 @@ variables:
   image: rustlang/rust:nightly
   allow_failure: true  # It's not often, but it happens nightly breaks, surprisingly.
 
-.build:
-  stage: build
-  script:
-    - cargo build --verbose
-
 .test:
   stage: test
   script:
@@ -32,16 +26,6 @@ rustfmt:
   extends:
     - .stable
 
-stable-build:
-  extends:
-    - .build
-    - .stable
-
-nightly-build:
-  extends:
-    - .build
-    - .nightly
-
 stable-test:
   extends:
     - .test