Update to clap 3.* (#4082)

* Update to clap 3.0

This commit migrates all CLI commands internally used in this project
from structopt/clap2 to clap 3. The intent here is to ensure that we're
using maintained versions of the dependencies as structopt and clap 2
are less maintained nowadays. Most transitions were pretty
straightforward and mostly dealing with structopt/clap3 differences.

* Fix a number of `cargo deny` errors

This commit fixes a few errors around duplicate dependencies which
arose from the prior update to clap3. This also uses a new feature in
`deny.toml`, `skip-tree`, which allows having a bit more targeted
ignores for skips of duplicate version checks. This showed a few more
locations in Wasmtime itself where we could update some dependencies.

src/bin/wasmtime.rs

@@ -4,20 +4,15 @@
 //! See `wasmtime --help` for usage.
 
 use anyhow::Result;
-use structopt::{clap::AppSettings, clap::ErrorKind, StructOpt};
+use clap::{ErrorKind, Parser};
 use wasmtime_cli::commands::{
     CompileCommand, ConfigCommand, RunCommand, SettingsCommand, WastCommand,
 };
 
 /// Wasmtime WebAssembly Runtime
-#[derive(StructOpt)]
-#[structopt(
-    name = "wasmtime",
-    version = env!("CARGO_PKG_VERSION"),
-    global_settings = &[
-        AppSettings::VersionlessSubcommands,
-        AppSettings::ColoredHelp
-    ],
+#[derive(Parser)]
+#[clap(
+    version,
     after_help = "If a subcommand is not provided, the `run` subcommand will be used.\n\
                   \n\
                   Usage examples:\n\
@@ -34,7 +29,7 @@ use wasmtime_cli::commands::{
                   \n  \
                   wasmtime example.wasm --invoke add 1 2\n"
 )]
-enum WasmtimeApp {
+enum Wasmtime {
     // !!! IMPORTANT: if subcommands are added or removed, update `parse_module` in `src/commands/run.rs`. !!!
     /// Controls Wasmtime configuration settings
     Config(ConfigCommand),
@@ -48,7 +43,7 @@ enum WasmtimeApp {
     Wast(WastCommand),
 }
 
-impl WasmtimeApp {
+impl Wasmtime {
     /// Executes the command.
     pub fn execute(self) -> Result<()> {
         match self {
@@ -62,14 +57,13 @@ impl WasmtimeApp {
 }
 
 fn main() -> Result<()> {
-    WasmtimeApp::from_iter_safe(std::env::args())
-        .unwrap_or_else(|e| match e.kind {
-            ErrorKind::HelpDisplayed
-            | ErrorKind::VersionDisplayed
-            | ErrorKind::MissingArgumentOrSubcommand => e.exit(),
-            _ => WasmtimeApp::Run(
-                RunCommand::from_iter_safe(std::env::args()).unwrap_or_else(|_| e.exit()),
-            ),
+    Wasmtime::try_parse()
+        .unwrap_or_else(|e| match e.kind() {
+            ErrorKind::DisplayHelp
+            | ErrorKind::DisplayVersion
+            | ErrorKind::MissingSubcommand
+            | ErrorKind::MissingRequiredArgument => e.exit(),
+            _ => Wasmtime::Run(RunCommand::parse()),
         })
         .execute()
 }