Relative links in tasks output, truncated export cmd in terminal

[brianignacio5]

Fix #333

Fix #266

Fix #329

Use vscode ShellExecution to fix relative paths link in build/flash task outputs. PTAL @boarchuz

Remove export cmd and use strict env for Monitor terminal and ESP-IDF Terminal . PTAL @resetnow

Fix closing monitor issues when flash is trigger. PTAL @seulater

[vlad-ivanov-name]

@brianignacio5 thank you for the update, I tested this PR and I'm observing the following:

1. after a fresh start, monitor command works 🎉
2. after a fresh start, build-flash-monitor sequence works
3. unfortunately, if the monitor is running and I'm trying to flash, there will be an error:

I think the reason is that the serial resource is not released quickly enough - perhaps the terminal is closed or the process is killed asynchronously?

If I retry immediately after this error, it will flash successfully.

[brianignacio5]

I think is about giving enough time for monitor to be disposed. Will check if we have access to terminal disposed event and exit status, timeout is a tricky thing, otherwise just add a timeout configuration setting for this.

Please try again @resetnow, after last commit (2677315) I can't reproduce anymore.

[vlad-ivanov-name]

This works better - I haven't been able to find any problems