Added information on --cap-lints to deny-warnings antipattern (#58)

* added information on --cap-lints to deny-warnings antipattern

Co-authored-by: simonsan <14062932+simonsan@users.noreply.github.com>
Co-authored-by: Marco Ieni <11428655+MarcoIeni@users.noreply.github.com>

anti_patterns/deny-warnings.md

@@ -36,7 +36,10 @@ All this conspires to potentially break the build whenever something changes.
 
 Furthermore, crates that supply additional lints (e.g. [rust-clippy]) can no
 longer be used unless the annotation is removed. This is mitigated with
-[--cap-lints].
+[--cap-lints]. The `--cap-lints=warn` command line argument, turns all `deny`
+lint errors into warnings. But be aware that `forbid` lints are stronger than
+`deny` hence the 'forbid' level cannot be overridden to be anything lower than
+an error. As a result `forbid` lints will still stop compilation.
 
 ## Alternatives
 
@@ -45,7 +48,7 @@ setting from the code, and second, we can name the lints we want to deny
 explicitly.
 
 The following command line will build with all warnings set to `deny`:
- 
+
 ```RUSTFLAGS="-D warnings" cargo build```
 
 This can be done by any individual developer (or be set in a CI tool like