[libdmapsharing] .gitlab-ci.yml: adjust ARM values

[W. Michael Petullo <wmpetullo src gnome org>]

commit c4357e5c9f68db13986b450a60607434ea38c2cd
Author: W. Michael Petullo <mike flyn org>
Date:   Fri Jul 3 18:06:42 2020 -0500

    .gitlab-ci.yml: adjust ARM values

 .gitlab-ci.yml | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 8e13799..52d84fe 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -17,7 +17,13 @@ build-ubuntu:
     - make clean
 
 build-alpine:
-  image: arm32v7/alpine:latest
+  image: arm64v8/alpine:latest
+
+  tags:
+    - aarach64
+
+  variables:
+    ARCH: aarch64
 
   before_script:
     - apk update