Azure Pipelines: simplify test job definitions
    
    Rewrite templates to make test job declarations simpler and easier to
    work with.
    
    A test job template can be instantiated this way:
    
    - template: templates/test-jobs.yml
      parameters:
        jobName: Base
        jobTitle: Base tests
        testsToRun:
        - test_cmdline
        - test_install
        - test_ipaclient
        - test_ipalib
        - test_ipaplatform
        - test_ipapython
        testsToIgnore:
        - test_integration
        - test_webui
        - test_ipapython/test_keyring.py
        taskToRun: run-tests
    
    Both 'testsToRun' and 'testsToIgnore' accept arrays of test matches.
    Wildcards also supported:
    
        ....
        testsToRun:
        - test_xmlrpc/test_hbac*
        ....
    
    'taskToRun' specifies a script ipatests/azure/azure-${taskToRun}.sh that
    will be executed in the test environment to actually start tests.
    
    Parameters 'testsToRun' and 'testsToIgnore' define TESTS_TO_{RUN,IGNORE}
    variables that will be set in the environment of the test script. These
    variables will have entries from the parameters separated by a space.
    
    Reviewed-By: Christian Heimes <cheimes@redhat.com>