SLING-8980 - Set bundle-version suffix of SNAPSHOT versions to the static String "-SNAPSHOT" instead of a timestamp

This ensures that we will get reproducible builds for SNAPSHOT builds as well.

The '.SNAPSHOT' qualifier is supported by the OSGi installer, so there is no loss
of functionality.
diff --git a/sling-bundle-parent/pom.xml b/sling-bundle-parent/pom.xml
index 4e1199d..8673fba 100644
--- a/sling-bundle-parent/pom.xml
+++ b/sling-bundle-parent/pom.xml
@@ -72,7 +72,7 @@
 
 # overwrite timestamp format used as qualifier for snapshots to make the resolution higher (i.e. make them differ for each build), 
 # compare with https://www.mail-archive.com/dev@sling.apache.org/msg76177.html
--snapshot: ${tstamp;yyyyMMddHHmmssSSS}
+-snapshot: SNAPSHOT
 
 # reproducible builds (https://github.com/bndtools/bnd/issues/3521)
 -noextraheaders: true