experiment: set CARGO_TERM_VERBOSE to false explicitly

src/snapshot_tests.rs

@@ -140,7 +140,7 @@ fn assert_integration_test(test_name: &str, invocation: &[&str]) {
     std::env::remove_var("RUST_BACKTRACE");
     // remove the cargo verbosity variable, which gets passed to `cargo doc`
     // and may create a nonreproducible environment.
-    std::env::remove_var("CARGO_TERM_VERBOSE");
+    std::env::set_var("CARGO_TERM_VERBOSE", "false");
 
     let stdout = StaticWriter::new();
     let stderr = StaticWriter::new();