Merge pull request scala#10500 from SethTisue/fix-spec-build

Author: SethTisue

.travis.yml

@@ -46,8 +46,7 @@ jobs:
 
       # build the spec using jekyll
       - stage: build
-        # bionic for newer ruby ("bundler requires Ruby version >= 2.6.0")
-        dist: bionic
+        dist: focal
         language: ruby
         # ruby 3.x is default, need to upgrade jekyll. using 2.7 for now.
         rvm: 2.7