Make as prerelease, not with metadata.

.travis.yml

@@ -14,7 +14,7 @@ branches:
   only:
     - master
     # enable building tags
-    - /^v\d+\.\d+(\.\d+)?(\+[^-]+)?(-\S*)?$/
+    - /^v\d+\.\d+(\.\d+)?(-\S*)?$/
 
 cache:
   npm: true

package.json

@@ -1,6 +1,6 @@
 {
   "name": "osrm",
-  "version": "5.22.0+customsnapping.5",
+  "version": "5.22.0-customsnapping.1",
   "private": false,
   "description": "The Open Source Routing Machine is a high performance routing engine written in C++14 designed to run on OpenStreetMap data.",
   "dependencies": {