Use log crate instead of eprintln & remove some unwraps (#5010)

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- I fixed the TODO to use the `log` crate instead of `eprintln`
- Set the rust-version in the `scripts/check.sh` to the same as egui is
on
- I made xtask use anyhow to remove some unwraps 

* [x] I have followed the instructions in the PR template

xtask/src/utils.rs

@@ -34,7 +34,7 @@ pub fn ask_to_run(mut cmd: Command, ask: bool, reason: &str) -> Result<(), DynEr
             a => return Err(format!("Invalid answer `{a}`").into()),
         };
     } else {
-        eprintln!("Running `{cmd:?}` to {reason}.");
+        println!("Running `{cmd:?}` to {reason}.");
     }
 
     let status = cmd.status()?;