Define and use standardized language for the conformance tests

[kemerava]

Minor Issue

As discussed in #1426 the conformance tests all have different language, which I think would be nice to standardize.
Examples include using "App A does" or "App A can" or "B should" sometimes in the same test suit.
It is not a big issue so maybe if the tests are going to completely change, then we won't need it at all.

Area of Issue

• App Directory
• API
• Context Data
• Intents
• Desktop Agent Bridging
• Use Cases
• Other

Issue Description:

Standard language will make the test definitions in fdc3-conformance folder more readable