fix concurrency issues with replacing concurrent* to async*

[kukgini]

Checklist

• [x] have run AriesFrameworkTests
• [x] I have run AllTests

Description

fix concurrency issues with replacing concurrent to async

Related Issues

• 44

[conanoc]

It could fix the issue but I intended to use the concurrent version for efficiency. Can you create a test case that fails with the concurrent version? The test will also make sure that this change will fix that issue.

[kukgini]

@conanoc As you said, this solution sacrifices performance. However, I believe that improving performance through concurrency only makes sense if stability is achieved.

Unfortunately I don't know how to write a test case that will always fail in unit tests for race condition. Moreover, this error only happens intermittently in my app attached to the bcovrin testnet. AllTests that I do iteratively normally succeed.

[conanoc]

The test doesn't have to fail always. It's enough to fail sometimes. I'll also look at this later.

[conanoc]

50 has merged for this. Thanks for reporting the issue.