chore: ignore all target dirs (tokio-rs#150)

* chore: ignore all target dirs

The gitignore for this repository currently includes the pattern
`/*/target`, which will ignore all directories named `target` that are
nested up to one directory deep from the root. This ignores the target
dir for the workspace, and any generated by builds on individual
workspace crates. However, the `tracing` crate contains test crates
which cannot be part of the workspace, due to setting feature flags.
These crates are inside the `tracing` crate's subdirectory, so the
`target` dirs generated by running these tests are nested _two_ levels
deep. Git doesn't know to ignore the generated files from the test
dirs, which is kind of annoying.

This branch changes the ignore pattern to `/**/target`, which should
ignore _all_ subdirectories named `target`. This does have the potential
downside that if any crate adds a module called `target`, we'd have to
update the gitignore, but I'm not _too_ concerned currently.

Signed-off-by: Eliza Weisman <[email protected]>

Author: hawkw

.gitignore

@@ -32,8 +32,7 @@ Temporary Items
 ### Rust ###
 # Generated by Cargo
 # will have compiled files and executables
-/target/
-/*/target/
+target/
 
 # Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
 # More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html