Added specific VM tests

tests/test-simple-node-centos-7.yml

+---
+- hosts: localhost
+  connection: local
+  remote_user: root
+  tasks:
+  - name: Download paas-ci role
+    local_action: command ansible-galaxy install --force git+https://baltig.infn.it/infn-cloud/paas-ci.git
+    changed_when: false
+
+  - include_role:
+      name: paas-ci
+    vars:
+      paas_ci_test:
+        template_url: https://baltig.infn.it/infn-cloud/tosca-templates/-/raw/master/single-vm/single_vm.yaml
+        n_timeout_ticks: 90
+        inputs: |
+          '{ "os_distribution":"centos", "os_version": "7", "users": [{"os_user_add_to_sudoers": true, "os_user_name": "scans", "os_user_ssh_public_key": "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCmQvE3sXtg4D/KYzhCdP6cICvy5foeSkHenKTisxdGJK8L0cDmV+4k7fIah1GIXrldjQBGWHSTbIj1qRTXG2OPWFxeDoXIN1FyKxwdOgwIfzIRtVq18VZEqt9eOiNUXN8jGoEAgcU7obqXuPqKAndk4tyOnSDuVnfnZWAiesVvWK16GEq0PAxBhJoX3eq501ilsNnJZDMEnvQEgtFuIbADEanrhRV3yaEca+9vFyOQRkyxDF8Gn6P/wZ4oe35bdgXxi/hg8JVKYbDCLlT+Fdi+OC3trRhwCcBSvDFD0ZQ8oLemzUk+732TqR+I8gVjPE9fiNF+/mrj5OX55SDr8Qgf scans"}]}'
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tests/test-simple-node-ubuntu-20.04.yml

+---
+- hosts: localhost
+  connection: local
+  remote_user: root
+  tasks:
+  - name: Download paas-ci role
+    local_action: command ansible-galaxy install --force git+https://baltig.infn.it/infn-cloud/paas-ci.git
+    changed_when: false
+
+  - include_role:
+      name: paas-ci
+    vars:
+      paas_ci_test:
+        template_url: https://baltig.infn.it/infn-cloud/tosca-templates/-/raw/master/single-vm/single_vm.yaml
+        n_timeout_ticks: 90
+        inputs: |
+          '{ "os_distribution":"ubuntu", "os_version": "20.04", "users": [{"os_user_add_to_sudoers": true, "os_user_name": "scans", "os_user_ssh_public_key": "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCmQvE3sXtg4D/KYzhCdP6cICvy5foeSkHenKTisxdGJK8L0cDmV+4k7fIah1GIXrldjQBGWHSTbIj1qRTXG2OPWFxeDoXIN1FyKxwdOgwIfzIRtVq18VZEqt9eOiNUXN8jGoEAgcU7obqXuPqKAndk4tyOnSDuVnfnZWAiesVvWK16GEq0PAxBhJoX3eq501ilsNnJZDMEnvQEgtFuIbADEanrhRV3yaEca+9vFyOQRkyxDF8Gn6P/wZ4oe35bdgXxi/hg8JVKYbDCLlT+Fdi+OC3trRhwCcBSvDFD0ZQ8oLemzUk+732TqR+I8gVjPE9fiNF+/mrj5OX55SDr8Qgf scans"}]}'
\ No newline at end of file