ci: simplifiy matrix for sanitizer-linux job (#683)

Author: newpavlov

.github/workflows/tests.yml

@@ -144,16 +144,11 @@ jobs:
     runs-on: ${{ matrix.runner }}
     strategy:
       matrix:
-        arch: [
-            "aarch64",
-            "x86_64",
-        ]
         include:
           # MemorySanitizer won't run in QEMU so we can't run it in cross:
           # https://github.com/llvm/llvm-project/issues/65144
           - arch: aarch64
             runner: ubuntu-24.04-arm
-
           - arch: x86_64
             runner: ubuntu-24.04
     steps: