Revert ".travis.yml: Use Ubuntu 20.04 "Focal" environment"

This reverts commit 4d59c1a00d. Something's wrong with Java 8 in Travis's Ubuntu Focal environment: Expected feature release number in range of 9 to 16, but got: 8
2020-12-08 08:55:27 +02:00 · 2020-12-08 08:55:27 +02:00 · 112cb8a133
parent 4d59c1a00d
commit 112cb8a133
1 changed files with 1 additions and 1 deletions
--- a/.travis.yml
+++ b/.travis.yml
@ -1,4 +1,4 @@
-dist: focal
+dist: bionic
 language: java
 jdk:
  - openjdk8