Remove Xcode 15 validation

Author: maxep

.gitlab-ci.yml

@@ -267,25 +267,6 @@ SPM Build (Swift 5.10):
  - make spm-build-macos
  - make spm-build-watchos
 
-SPM Build (Swift 5.9):
- stage: smoke-test
- rules: 
- - !reference [.test-pipeline-job, rules]
- - !reference [.release-pipeline-job, rules]
- tags:
- - macos:ventura
- - specific:true
- variables:
- XCODE: "15.2.0"
- script:
- - ./tools/runner-setup.sh --xcode "$XCODE" --iOS --tvOS --visionOS --watchOS
- - make clean repo-setup ENV=ci
- - make spm-build-ios
- - make spm-build-tvos
- - make spm-build-visionos
- - make spm-build-macos
- - make spm-build-watchos
-
 SPI Docs Build:
  stage: lint
  rules: