test insert triggers for g-x-g relations

[kortemik]

test case where a host gets two tags because:

• capture group A is created
• capture group B is created
• host group X is created
• host group Y is created
• host is created
• host is added to host group X and Y
• host group X is added to capture group A
• host group Y is added to capture group B
• tag N is added to capture group A
• tag N is added to capture group B -> should throw duplicate tag for a host

Originally posted by @kortemik in #207 (comment)

[kortemik]

test
plural tags from tag insert to capture-group
plural tags from host insert to host-group
plural tags from new g-x-g linkage