Update the default Cargo.toml produced by cargo verus new to only list

vstd as a dependency.

Author: parno

source/cargo-verus/src/main.rs

@@ -103,8 +103,6 @@ edition = "2021"
 
 [dependencies]
 vstd = { git = "https://github.com/verus-lang/verus", rev = "BUILDREV" }
-builtin = { git = "https://github.com/verus-lang/verus", rev = "BUILDREV" }
-builtin_macros = { git = "https://github.com/verus-lang/verus", rev = "BUILDREV" }
 
 [package.metadata.verus]
 verify = true