Add negative automated test to verify a situation when application selection is provided with conflicting resource reference and matching labels

Description

The scenario:

• Create an application #1 in a form of Deployment set matching labels on it
• Create an application #2 in a form of Deployment set different matching labels on it
• Create a backing service (PostgreSQL DB) instance
• Create ServiceBindingRequest with both resourceRef=app1 and matchLabels pointing to App #2's matching labels
• Verify that the operator handles this situation without crashing or coming into an infinite loop - according to the operator's function

Acceptance Criteria

• A new test is added to be executed by the

  make test-unit

  command so it can be executed on CI.