Address the warning in job build of workflow Rust

rust-lang/edition-guide#267
The resolver is a global setting for a [workspace], and the setting is ignored in dependencies.
 The setting is only honored for the top-level package of the workspace.

Author: holdennguyen

Cargo.toml

@@ -1,8 +1,10 @@
 [workspace]
+resolver = "2"
+
 members = [
     "01-cli-tool",
     "02-agent",
     "03-api",
     "04-frontend",
     "05-backend",
-]
+]