daca@home: update OLD_VERSION and SERVER_VERSION [skip ci] (danmar#8294)

Author: danmar

tools/donate-cpu-server.py

@@ -26,10 +26,10 @@
 # Version scheme (MAJOR.MINOR.PATCH) should orientate on "Semantic Versioning" https://semver.org/
 # Every change in this script should result in increasing the version number accordingly (exceptions may be cosmetic
 # changes)
-SERVER_VERSION = "1.3.67"
+SERVER_VERSION = "1.3.68"
 
 # TODO: fetch from GitHub tags
-OLD_VERSION = '2.19.0'
+OLD_VERSION = '2.20.0'
 
 HEAD_MARKER = 'head results:'
 INFO_MARKER = 'info messages:'