feat(coverage): Register coverage.py to hermetic toolchains (#977)

This allows including the coverage package as part of the toolchain dependencies, which is mixed into a test's dependencies when `bazel coverage` is run (if coverage is not enabled, no extra dependency is added)

For now, it's disabled by default because enabling it poses the risk of having two versions of coverage installed (one from the toolchain, one from the user's dependencies).

The user can turn the coverage_tool setting by passing
`register_coverage_tool=(True|False)` to `python_register_toolchains` or
`python_register_multi_toolchains` call or specifying the
`coverage_tool` label as described in the `versions.bzl` file.

Use coverage.py v6.5.0 because the latest has `types.py` in the package
directory, which imports from Python's stdlib `types` [1]. Somehow the
Python interpreter is thinking that the `from types import FrameType` is
referring to the currently interpreted file and everything breaks. I
would have expected the package to use absolute imports and only attempt
to import from `coverage.types` if we use `coverage.types` and not just
a plain `types` import.

NOTE: Coverage is only for non-windows platforms.

Update tests to:
- ensure that we can still use the toolchain as previously.
- ensure that we are not downloading extra deps if they are not needed.

* Also changes the projects bazelrc to use a remotejdk, which makes it easier for contributors because they don't have to locally install a jdk to get going.

[1]: https://github.com/nedbat/coveragepy/blob/master/coverage/types.py
[3]: https://github.com/bazelbuild/bazel/issues/15835

examples/multi_python_versions/WORKSPACE

diff --git a/examples/multi_python_versions/WORKSPACE b/examples/multi_python_versions/WORKSPACE
index 41c8880..35855ca 100644
--- a/examples/multi_python_versions/WORKSPACE
+++ b/examples/multi_python_versions/WORKSPACE
@@ -22,11 +22,14 @@
         "3.8",
         "3.9",
         "3.10",
+        "3.11",
     ],
+    register_coverage_tool = True,
 )
 
 load("@python//:pip.bzl", "multi_pip_parse")
 load("@python//3.10:defs.bzl", interpreter_3_10 = "interpreter")
+load("@python//3.11:defs.bzl", interpreter_3_11 = "interpreter")
 load("@python//3.8:defs.bzl", interpreter_3_8 = "interpreter")
 load("@python//3.9:defs.bzl", interpreter_3_9 = "interpreter")
 
@@ -35,11 +38,13 @@
     default_version = default_python_version,
     python_interpreter_target = {
         "3.10": interpreter_3_10,
+        "3.11": interpreter_3_11,
         "3.8": interpreter_3_8,
         "3.9": interpreter_3_9,
     },
     requirements_lock = {
         "3.10": "//requirements:requirements_lock_3_10.txt",
+        "3.11": "//requirements:requirements_lock_3_11.txt",
         "3.8": "//requirements:requirements_lock_3_8.txt",
         "3.9": "//requirements:requirements_lock_3_9.txt",
     },