revert/restore skip building for armv7 not linking examples

[ 50%] Building C object CMakeFiles/testdelay.dir/examples/testdelay.c.o
[ 54%] Linking C executable bin/testdelay
/usr/bin/ld: lib/libtask.a(task.c.o): in function `taskcreate':
task.c:(.text+0x1ea): undefined reference to `getmcontext'
/usr/bin/ld: lib/libtask.a(context.c.o): in function `swapcontext':
context.c:(.text+0x82): undefined reference to `getmcontext'
/usr/bin/ld: context.c:(.text+0x90): undefined reference to `setmcontext'
collect2: error: ld returned 1 exit status

.github/workflows/ci_qemu.yml

@@ -10,33 +10,23 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - target: arm
-            arch: armv6
-            distro: buster
-          - target: arm
-            arch: armv7
-            distro: archarm_latest
           - target: aarch64
             arch: aarch64
-            distro: ubuntu_latest
           - target: ppc64v2
             arch: ppc64le
-            distro: ubuntu_latest
           - target: riscv64
             arch: riscv64
-            distro: ubuntu_latest
           - target: s390x
             arch: s390x
-            distro: ubuntu_latest
     steps:
       - uses: actions/checkout@v3
       - uses: uraimo/run-on-arch-action@v2
         with:
           arch: ${{ matrix.arch }}
-          distro:  ${{ matrix.distro }}
+          distro:  ubuntu_latest
           install: |
             apt-get update -q -y
-            apt-get install -q -y cmake build-essential
+            apt-get install -q -y --no-install-recommends cmake build-essential
           env: |
             # Valgrind on arm will fail if the stack size is larger than 8MB.
             # Set QEMUs stack size to 8MB since Github runners use 16MB default.