Remove docker armv7 build (#953)

AMD64 is the most supported cpu architecture, and ARM64 is used in
modern apple laptops and some other devices.

armv7 is not supported by the major platforms as this is an old 32 bit
cpu. I think nobody is actually using this.

Author: jaapio

.github/workflows/docker.yaml

@@ -18,7 +18,6 @@ jobs:
       matrix:
         platform:
           - linux/amd64
-          - linux/arm/v7
           - linux/arm64
     steps:
       - uses: actions/checkout@v4