chore: drop obsolete part of gitignore (#5260)

Co-authored-by: Sandi Fatic <sandi.fatic@gmail.com>
Co-authored-by: Bowen Wang <bowenwang1996@users.noreply.github.com>

.gitignore

@@ -12,10 +12,6 @@ docker-build
 /chain/client/tmp_bench
 testdir/
 
-# 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
-core/wasm/**/Cargo.lock
-
 # These are backup files generated by rustfmt
 **/*.rs.bk