This saves developers from having to install a dependency. It also
allows us to drop an old Github Actions dependency that hasn't been
updated in 2 years. This is the standard practice for projects using
Mill on Github.

Node 16 is deprecated and will eventually stop being supported.

* - add probe IOs to FixedIOModuleSpec
* getMatchedFields: don't recurse through probes.
* update scaladoc for FlatIO for probe types

---------

Co-authored-by: Will Dietz <will.dietz@sifive.com>

Also fix reifySingleData to return the Data itself if it is not a view.

Expected result is fully aligned, which is what happens
when reading from a probe.

When the source is already at the LCA (from parent)
there's no probe and the secret connections only support
a few commands.

For lack of a way to do, e.g., `:#=` here,
use `read(probe(x))` to get the fully aligned result
that's expected and bored down to the child.

This isn't ideal but fixes this using only the sorts of expressions
and commands that we've already committed to supporting.

Fixes #3557.

This should always return the same type/alignment regardless of where
the original resides, so if the expectation is a fully aligned result
then create one if needed.

* Fix widths for literal values in Bundle literals

Previously, the user-specified (or unspecified minimum width) of the
literal would be used in some operations like concatenation.

* Implicitly truncate too-wide literals in Bundle literals

This is to fix a bug in concatenation without breaking things relying on
implicit truncation. This will be a warning in newer versions of Chisel.

Fixes muxing of Aggregate views, and fixes ProbeValues of Aggregate
views.

* add toRelativeTargetToHierarchy
* add tests for toRelativeTargetToHierarchy

Also remove line and column when a message is provided.

Previously, a view of an empty Record or Vec would always have a
litValue of 0.

Also tweak Vec.Lit code to use cloneAsSuperType rather than implementing
its own version of the same concept.

This is an automated commit generated by the `circt/update-circt` GitHub
Action.

Co-authored-by: chiselbot <chiselbot@users.noreply.github.com>

While these tests pass, they generate invalid FIRRTL
that firtool would reject.  Rewrite without using input probes.

* type equivalence includes probe
* Add type equivalence checks for Probes, including writeability and color.

* scalatest: 3.2.14 => 3.2.18
* scalacheck-1-16:3.2.14.0 => scalacheck-1-18:3.2.18.0
* json4s-native: 4.0.6 => 4.0.7
* commons-text: 1.10.0 => 1.12.0
* os-lib: 0.9.1 => 0.10.0
* upickle: 3.1.0 => 3.3.0

* Delete moultingyaml, it has been unused for a long time
* Make Mill versions consistent with SBT versions

It should never have been a public API

Tiny cleanup of the test once the name of the function changed

The DataMirror API allows users who know what they're doing to access a module's ports before it is closed.