[SOL] tests: update docker image name

Author: alessandrod

.github/workflows/ci.yml

@@ -190,7 +190,7 @@ jobs:
           - name: mingw-check
             os: ubuntu-latest
             env: {}
-          - name: x86_64-gnu-llvm-10
+          - name: x86_64-gnu-llvm-12
             os: ubuntu-latest
             env: {}
           - name: sbf-solana-solana

src/ci/github-actions/ci.yml

@@ -383,7 +383,7 @@ jobs:
           - name: mingw-check
             <<: *job-linux-xl
 
-          - name: x86_64-gnu-llvm-10
+          - name: x86_64-gnu-llvm-12
             <<: *job-linux-xl
 
           - name: sbf-solana-solana