Add basic test of the input file option

Author: fila43

tests/simple.sql

@@ -0,0 +1,5 @@
+CREATE TABLE mytable(
+        mynumber int,
+        name varchar(255)
+);
+INSERT INTO mytable VALUES (1, 'test');

tests/tests_input_file.yml

@@ -0,0 +1,26 @@
+- name: Ensure that the role runs with input file
+  hosts: all
+  gather_facts: false
+
+  tasks:
+    - name: Run postgresql role with input file
+      include_role:
+        name: linux-system-roles.postgresql
+      vars:
+        postgresql_input_file: simple.sql
+
+    - meta: flush_handlers
+
+    - name: Get content of database
+      become: yes
+      become_user: postgres
+      shell: |
+        set -euo pipefail
+        echo "SELECT * FROM mytable;" | psql
+      register: result
+      changed_when: false
+
+    - name: Check content of databse
+      assert:
+        that: >
+          "1 row" in result.stdout