Support "true" and "false" (and "YES" and "NO" in Objective-C) in
ValueObject::SetValueFromCString.

Fixes #112597

This uses [teyit](https://pypi.org/project/teyit/) to modernize asserts,
as recommended by the [unittest release
notes](https://docs.python.org/3.12/whatsnew/3.12.html#id3).

For example, `assertTrue(a == b)` is replaced with `assertEqual(a, b)`.
This produces better error messages, e.g. `error: unexpectedly found 1
and 2 to be different` instead of `error: False`.

assertEquals is a deprecated alias for assertEqual and has been removed
in Python 3.12. This wasn't an issue previously because we used a
vendored version of the unittest module. Now that we use the built-in
version this gets updated together with the Python version used to run
the test suite.

This is an ongoing series of commits that are reformatting our Python
code. Reformatting is done with `black` (23.1.0).

If you end up having problems merging this commit because you have made
changes to a python file, the best way to handle that is to run `git
checkout --ours <yourfile>` and then reformat it with black.

RFC: https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style

Differential revision: https://reviews.llvm.org/D151460

Commit 92f0e4cca introduced test file with name TestChangeValue.py,
which leads to test failure because there already is a test files with the same name
In this commit a newly added file is renamed to fix this failure

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D140624

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D140623

Eliminate boilerplate of having each test manually assign to `mydir` by calling
`compute_mydir` in lldbtest.py.

Differential Revision: https://reviews.llvm.org/D128077

Add a function to make it easier to debug a test failure caused by an
unexpected state.

Currently, tests are using assertEqual which results in a cryptic error
message: "AssertionError: 5 != 10". Even when a test provides a message
to make it clear why a particular state is expected, you still have to
figure out which of the two was the expected state, and what the other
value corresponds to.

We have a function in lldbutil that helps you convert the state number
into a user readable string. This patch adds a wrapper around
assertEqual specifically for comparing states and reporting better error
messages.

The aforementioned error message now looks like this: "AssertionError:
stopped (5) != exited (10)". If the user provided a message, that
continues to get printed as well.

Differential revision: https://reviews.llvm.org/D127355

Replace forms of `assertTrue(err.Success())` with `assertSuccess(err)` (added in D82759).

* `assertSuccess` prints out the error's message
* `assertSuccess` expresses explicit higher level semantics, both to the reader and for test failure output
* `assertSuccess` seems not to be well known, using it where possible will help spread knowledge
* `assertSuccess` statements are more succinct

Differential Revision: https://reviews.llvm.org/D119616