close closeable clients rule

[Njeriiii]

What does this implement/fix? Explain your changes.

This class contains the inspection tool for checking if Closeable clients are properly closed.
It checks if the Closeable client is declared in a try-with-resources block or if it is closed in the code block.
If the Closeable client is not closed, it registers a problem with the ProblemsHolder.
currently can identify closeable clients in the PSI tree

Has this been tested?

• Tested

Any relevant logs, screenshots, error output, etc.?

[samvaity]

Is this working now?
Also, did you figure out unit tests?

[lmolkova]

would it detect issues if I do this:

void doStuff() {
    Client client = createClient();
    // it's ok if we can't detect all possible cases when variable is reassigned multiple times
}

Client createClient() {
  Client c = new Client();
  ...
  return  c;
}

or

void doStuff() {
    Client client = createClient();
    // important that we don't report issue here
    client.close();
}

Client createClient() {
  Client c = new Client();
  ...
  return  c;
}

?