(GH-1152) Define cargo workspace

Prior to this change, the project didn't use a cargo workspace.
Instead, every crate independently managed its dependencies and
we associated crates with Rust Analyzer in VS Code through the
configuration settings.

This change:

- Defines a virtual workspace at the repository root, including
  every crate as a workspace member, defining the release profile,
  and defining every crate dependency.
- Updates the cargo manifest for every crate to inherit their
  dependencies from the workspace.
- Replaces the per-crate cargo lock files with the workspace-level
  lock file. Now dependency management happens with a single manifest
  and lock file.
- Makes minor changes to the build script to ensure functionality
  continues as previously defined.

Note that this change on its own doesn't drastically improve build
times. For build times to improve substantially, we need to:

1. Restructure the build to compile all crates with a single command.
   When we use `cargo build` at the repository root or the `--workspace`
   flag, cargo builds every crate and its dependencies together. Cargo
   uses the dependency graph to only compile each dependency crate once
   during the build, instead of recompiling every dependency when we
   compile on a crate-by-crate basis.
1. Enable the use of caching, like with `sccache`. When we enable cached
   builds, only crates that have been modified since the last build will
   be recompiled. This _substantially_ improves build times for local
   development and when we invoke tests after initial compilation.

However, both of these changes require more substantial modifications to
the build script, so they aren't addressed in this change. Those changes
will be addressed in a future commit.

Author: michaeltlombardi

.vscode/settings.json

@@ -1,16 +1,4 @@
 {
-    "rust-analyzer.linkedProjects": [
-        "./dsc/Cargo.toml",
-        "./dsc_lib/Cargo.toml",
-        "./dscecho/Cargo.toml",
-        "./osinfo/Cargo.toml",
-        "./registry/Cargo.toml",
-        "./runcommandonset/Cargo.toml",
-        "./tools/test_group_resource/Cargo.toml",
-        "./tools/dsctest/Cargo.toml",
-        "./tree-sitter-dscexpression/Cargo.toml",
-        "./y2j/Cargo.toml"
-    ],
     "rust-analyzer.showUnlinkedFileNotification": true,
     "json.schemas": [
         {