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

Cargo.lock

@@ -3155,6 +3155,7 @@ version = "0.1.0"
 dependencies = [
  "eframe",
  "env_logger",
+ "log",
  "puffin",
  "puffin_http",
 ]
@@ -3583,6 +3584,7 @@ version = "0.1.0"
 dependencies = [
  "eframe",
  "env_logger",
+ "log",
 ]
 
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