[CI] Functional: Increase Ulimit to 4096

Functional tests started to fail with
"Too many open files" randomly, the default ulimit in
OS is configured to 1024, increasing this to 4096
to avoid these random failures.

Closes-Bug: #2080199
Change-Id: Iff86599678ebdd5189d5b56d11f3373c9b138562
(cherry picked from commit 6970f39)
(cherry picked from commit b4241e3)
Conflicts:
	roles/configure_functional_tests/tasks/main.yaml

Author: elajkat

roles/configure_functional_tests/tasks/main.yaml

@@ -45,5 +45,9 @@
         fi
 
         configure_host_for_func_testing
+        echo "$USER soft nofile 4096" | sudo tee /etc/security/limits.d/99-user.conf
 
     executable: /bin/bash
+
+- name: Reset ssh connection to pick up limits
+  meta: reset_connection