Launchable

Support `launchable inspect tests --test-session-id <id>` command https://github.com/launchableinc/cli/pull/293

Update pytest support.

Add validation to the launchable record build command https://github.com/launchableinc/cli/pull/292

Add inspect command to confirm subset result.
Usage: `launchable inspect subset --subset-id <subset id>`

* Status message improvements
* User agent format fix

Improve cli outputs like below

- launchable record tests

$ launchable record build --name cli
Launchable uploaded 8 commits from repository /launchableinc/cli
Launchable recorded build cli to workspace launchableinc/cli with commits from 1 repository

| Name | Path | HEAD Commit |
|--------|--------|------------------------------------------|
| . | . | 4729a34fffae4f6d6190288466e3826c5f3dd488 |


- launchable subset


$ find -f tests/**/test_*.py | launchable subset --build cli --target 50% file > subset.txt
Your model is currently in training
Launchable created subset 1379 for build cli (test session 305) in workspace launchableinc/cli

| | Candidates | Estimated duration (%) | Estimated duration (min) |
|-----------|--------------|--------------------------|----------------------------|
| Subset | 16 | 50 | 0.000266667 |
| Remainder | 16 | 50 | 0.000266667 |
| | | | |
| Total | 32 | 100 | 0.000533333 |


- launchable record tests


$ launchable record tests --build cli file ./test-results/*.xml
Launchable recorded tests for build cli (test session 306) to workspace launchableinc/cli from 30 files:

| File found | Tests found | Test passed | Test failed | Total duration(min) |
|--------------|---------------|---------------|---------------|-----------------------|
| 30 | 86 | 84 | 2 | 0.0601 |