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.

cranelift/isle/islec/Cargo.toml

@@ -8,6 +8,6 @@ publish = false
 
 [dependencies]
 cranelift-isle = { version = "*", path = "../isle/" }
-env_logger = { version = "0.8", default-features = false }
+env_logger = { version = "0.9", default-features = false }
 miette = { version = "3.0.0", features = ["fancy"] }
-structopt = "0.3.23"
+clap = { version = "3.1.12", features = ["derive"] }

cranelift/isle/islec/src/main.rs

@@ -1,3 +1,4 @@
+use clap::Parser;
 use cranelift_isle::{compile, lexer, parser};
 use miette::{Context, IntoDiagnostic, Result};
 use std::{
@@ -5,17 +6,16 @@ use std::{
     io::{self, Write},
     path::PathBuf,
 };
-use structopt::StructOpt;
 
-#[derive(StructOpt)]
+#[derive(Parser)]
 struct Opts {
     /// The output file to write the generated Rust code to. `stdout` is used if
     /// this is not given.
-    #[structopt(short, long, parse(from_os_str))]
+    #[clap(short, long)]
     output: Option<PathBuf>,
 
     /// The input ISLE DSL source files.
-    #[structopt(parse(from_os_str), required(true))]
+    #[clap(required = true)]
     inputs: Vec<PathBuf>,
 }
 
@@ -32,7 +32,7 @@ fn main() -> Result<()> {
         )
     }));
 
-    let opts = Opts::from_args();
+    let opts = Opts::parse();
 
     let lexer = lexer::Lexer::from_files(opts.inputs)?;
     let defs = parser::parse(lexer)?;