CI: Split sed command to trigger a "dirty" state

There is no point in requesting a --dirty'd description when all you
have is a clean checkout.

.gitlab-ci.yml

@@ -16,9 +16,10 @@ archive:
   - apt-get update --quiet
   - apt-get install --quiet --assume-yes libsane-dev
   script:
-  - build=$(git describe --dirty --match '1.*' | sed 's/.*\.//; s/-.*//');
+  - build=$(git describe --match '1.*' | sed 's/.*\.//; s/-.*//');
+    sed -i "/^V_BUILD/s/=.*/=$build/" configure.in;
     extra=$(git describe --dirty --match '1.*' | sed 's/^[^-]*//');
-    sed -i "/^V_BUILD/s/=.*/=$build/; /^V_EXTRA/s/=.*/=$extra/" configure.in
+    sed -i "/^V_EXTRA/s/=.*/=$extra/" configure.in
   - autoconf --force
   - ./configure
   - make dist