When multiline message is logged, indent all but the first line (which
will be preceeded by the LOG_FORMAT). This improves the clarity of logs,
as it's immediately clear which lines are regular log output, and which
ones are multiline debug output.
Adjust the isctest.run.cmd() stdout/stderr logging to this new format.
For duration measurements, i.e. deadlines and timeouts, it's more
suitable to use monotonic time as it's guaranteed to only go forward,
unlike time.time() which can be affected by local clock settings.
Allow use of exception (and by extension, assert statements) in the
called function in order to extract essential debug information about
the type of failure that was encountered.
In case the called function fails to succeed on the last retry and
raised an exception, log it as error and set it as the assert message to
propagate it through the pytest framework.
In some cases, the numeric identifier doesn't correspond to the
directory name (i.e. `resolver` server in `shutdown` test, which is
supposed to be 10.53.0.3). These are typically servers that shouldn't be
auto-started by the runner, thus avoiding the typical `*ns<X>` name.
Support these server by allowing a fallback initialization with custom
numeric identifier in case it can't be parsed from the directory name.
Previously, these functions have been provided as fixtures. This was
limiting re-use, because it wasn't possible to call these outside of
tests / other fixtures without passing these utility functions around.
Move them into isctest.run package instead.
Enforcing pylint standards and default for our test code seems
counter-productive. Since most of the newly added code are tests or is
test-related, encountering these checks rarely make us refactor the code
in other ways and we just disable these checks individually. Code that
is too complex or convoluted will be pointed out in reviews anyways.
