Update flatcar-postinst

Co-authored-by: Krzesimir Nowak <[email protected]>

Author: pothos

flatcar-postinst

@@ -53,7 +53,7 @@ sysext_download() {
     local target="$2" # Path to write the payload to, writing does not need to be atomic because the caller later does an atomic move
     local from="$3" # Either path to XML dump or the constant "release-server"
     local target_tmpdir=""
-    local extracted_filename="${name/.gz/.raw}"
+    local extracted_filename="${name/%.gz/.raw}"
     local ARG=()
     local ret
     SUCCESS=false