testing/shfmt: Honor alpine pkver style

While not yet documented, Alpine favors to use plain semver where
possible for pkgver. Lets follow suit.

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
7 jobs for !792 with shfmt in 1 minute and 50 seconds (queued for 1 second)
latest detached
Status Job ID Name Coverage
  Lint
passed #8344
docker-alpine x86_64
lint

00:00:32

 
  Build
passed #8349
docker-alpine ci-build aarch64
build-aarch64

00:00:36

passed #8350
docker-alpine ci-build armv7
build-armv7

00:00:48

passed #8348
docker-alpine ci-build ppc64le
build-ppc64le

00:00:38

passed #8347
docker-alpine ci-build s390x
build-s390x

00:00:37

passed #8346
docker-alpine ci-build x86
build-x86

00:00:34

passed #8345
docker-alpine ci-build x86_64
build-x86_64

00:00:35