versions: Update go to 1.13.9

Update golang to 1.13.9 in versions.yaml.
In addition, add same golang version to `.travis.yml` and
delete the call to `.ci/install_go.sh` as it started to
cause problems in travis CI.

Fixes: #2592.

Signed-off-by: Salvador Fuentes <salvador.fuentes@intel.com>

.travis.yml

@@ -9,6 +9,8 @@ sudo: required
 dist: xenial
 
 language: go
+go:
+  - 1.13.9
 
 os:
   - linux
@@ -30,7 +32,6 @@ before_install:
   - ".ci/versions_checker.sh"
 
 before_script:
-  - ".ci/install_go.sh"
   - ".ci/static-checks.sh"
   - ".ci/versions_checker.sh"
 

versions.yaml

@@ -302,7 +302,7 @@ languages:
       description: |
         'newest-version' is the latest version known to work when
         building Kata
-      newest-version: "1.13.8"
+      newest-version: "1.13.9"
 
   rust:
     description: "rust language"