gitlab-ci: Add alpine to pipeline

[thuth: Enable "make check" tests, too, after tests/check-block.sh got fixed]

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-Id: <20210118063808.12471-10-jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2 files changed