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/commands/config.rs

@@ -1,35 +1,41 @@
 //! The module that implements the `wasmtime config` command.
 
 use anyhow::Result;
-use structopt::StructOpt;
+use clap::Parser;
 
 const CONFIG_NEW_AFTER_HELP: &str =
     "If no file path is specified, the system configuration file path will be used.";
 
 /// Controls Wasmtime configuration settings
-#[derive(StructOpt)]
-#[structopt(name = "run")]
-pub enum ConfigCommand {
+#[derive(Parser)]
+#[clap(name = "config")]
+pub struct ConfigCommand {
+    #[clap(subcommand)]
+    subcommand: ConfigSubcommand,
+}
+
+#[derive(clap::Subcommand)]
+enum ConfigSubcommand {
     /// Creates a new Wasmtime configuration file
-    #[structopt(after_help = CONFIG_NEW_AFTER_HELP)]
+    #[clap(after_help = CONFIG_NEW_AFTER_HELP)]
     New(ConfigNewCommand),
 }
 
 impl ConfigCommand {
     /// Executes the command.
     pub fn execute(self) -> Result<()> {
-        match self {
-            Self::New(c) => c.execute(),
+        match self.subcommand {
+            ConfigSubcommand::New(c) => c.execute(),
         }
     }
 }
 
 /// Creates a new Wasmtime configuration file
-#[derive(StructOpt)]
-#[structopt(name = "new", after_help = CONFIG_NEW_AFTER_HELP)]
+#[derive(Parser)]
+#[clap(name = "new", after_help = CONFIG_NEW_AFTER_HELP)]
 pub struct ConfigNewCommand {
     /// The path of the new configuration file
-    #[structopt(index = 1, value_name = "FILE_PATH")]
+    #[clap(index = 1, value_name = "FILE_PATH")]
     path: Option<String>,
 }