As a user, I can add Test Executions directly from the Test Plan

The user can add Test Executions right from the Test Plan view issue screen through a new button labeled 'Associate Test Executions'.

This button should be displayed under the Test Executions' section.

It should be possible to filter Test Executions by:

• label(s)
• component(s)
• FixVersion
• Test Environment(s)

Note: this will implicitly add the Tests of those Test Executions to the current Test Plan