doc: Add some build instructions to README

4 jobs for master in 56 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Container
passed #7293471
aarch64
build-container-aarch64

00:00:15

passed #7293470
build-container-x86_64

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  Build
passed #7293473
aarch64
build-aarch64

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passed #7293472
build-x86_64

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