[Tests] migrate installation_iojs test suite to GitHub Actions

Remove equivalent TravisCI entries

Signed-off-by: Jessica Wagantall <[email protected]>

.github/workflows/tests.yml

@@ -32,6 +32,7 @@ jobs:
           - install_script
           - sourcing
           - slow
+          - installation_iojs
         shell:
           - sh
           - bash

.travis.yml

@@ -87,13 +87,8 @@ env:
     - SHELL=bash TEST_SUITE=fast
     - SHELL=zsh TEST_SUITE=fast
     #  - SHELL=ksh TEST_SUITE=fast
-    - SHELL=sh TEST_SUITE=installation_iojs
     - SHELL=sh TEST_SUITE=installation_iojs WITHOUT_CURL=1
-    - SHELL=dash TEST_SUITE=installation_iojs
     - SHELL=dash TEST_SUITE=installation_iojs WITHOUT_CURL=1
-    - SHELL=bash TEST_SUITE=installation_iojs
     - SHELL=bash TEST_SUITE=installation_iojs WITHOUT_CURL=1
-    - SHELL=zsh TEST_SUITE=installation_iojs
     - SHELL=zsh TEST_SUITE=installation_iojs WITHOUT_CURL=1
-    #  - SHELL=ksh TEST_SUITE=installation_iojs
     #  - SHELL=ksh TEST_SUITE=installation_iojs WITHOUT_CURL=1