Add AK1008 - Check for multiple Stash.Stash() invocation

[Arkatufus]

Attempt to detect multiple Stash.Stash() invocation in a single code flow

Problems:

• To detect this, we would need ControlFlowGraph to be able to check all possible code flow
• ControlFlowGraph is an evolving API, there has been changes throughout the API versions
• Problems with IOperation.Children property renamed to IOperation.ChildOperations from Roslyn 3.11 to Roslyn 4
• Problems with analyzing inline anonymous lambda functions, this can only be done in Roslyn 4.9 which we don't support.