Use openjdk17, focal, upgrade bazel install scritp

.travis.yml

@@ -1,16 +1,18 @@
 language: java
 
 jdk:
-  - openjdk8
+  - openjdk17
 
-dist: trusty
+dist: focal
 
 os:
   - linux
 
 before_install:
-  - echo "deb [arch=amd64] https://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel.list
-  - curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add -
+  - sudo apt install apt-transport-https curl gnupg
+  - curl -fsSL https://bazel.build/bazel-release.pub.gpg | gpg --dearmor >bazel-archive-keyring.gpg
+  - sudo mv bazel-archive-keyring.gpg /usr/share/keyrings
+  - echo "deb [arch=amd64 signed-by=/usr/share/keyrings/bazel-archive-keyring.gpg] https://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel.list
   - sudo apt-get -qq update
   - sudo apt-get install -y bazel