[Test] Estimate time of java project build and run inside Che Code Editor in performance tests

[SkorikSergey]

What does this PR do?

This PR adds api load tests scripts that will be used in DevSpaces performance testing.

What issues does this PR fix or reference?

Openshift DevSpaces issue - Estimate time of java project build and run inside Che Code Editor in performance tests.

How to test this PR?

1. Create test users on cluster using performance-users job.
2. Api load test starts by command like:

./api-load-tests.sh -u user  -p load-user -s lombok -n 11 -c 1 -b https://devspaces.crw-qe.com -o https://api.ocp410.com:6443
    -u base username 
    -p common password 
    -b URL of DevSpaces 
    -o Openshift cluster URL
    -s test suite (by default its php)
    -n number of users ${NC} usernames will be set in format <username>1, <username>2(by default its 1) 
    -c count on how many times one user should run a workspace(by default its 1)

For now php, cpp, python, lombok and quarkus suites are available for testing.

3. Tests results adds to result.txt with format like:

Load testing for 11 users x 1 workspaces took 215 seconds
11 tests passed
0 tests failed
Workspace startup time: 
min: 37 second
avr: 44 second
max: 50 second
Project build time:
min: 140 second
avr: 142 second
max: 146 second

All logs from test pods saved in reports folder.

PR Checklist

As the author of this Pull Request I made sure that:

• The Eclipse Contributor Agreement is valid
• Code produced is complete
• Code builds without errors
• Tests are covering the bugfix or new feature
• The repository devfile is up to date and works
• Sections What issues does this PR fix or reference and How to test this PR completed
• Relevant user documentation updated
• Relevant contributing documentation updated
• CI/CD changes implemented, documented and communicated

Reviewers

Reviewers, please comment how you tested the PR when approving it.