feat: forbid certain usernames & room aliases

squashed from https://gitlab.com/famedly/conduit/-/merge_requests/582

Signed-off-by: strawberry <strawberry@puppygock.gay>

Cargo.toml

@@ -62,6 +62,9 @@ ring = "0.17.7"
 trust-dns-resolver = "0.23.2"
 # Used to find matching events for appservices
 regex = "1.10.3"
+# Used to load forbidden room/user regex from config
+serde_regex = "1.1.0"
+itertools = "0.12.1"
 # jwt jsonwebtokens
 jsonwebtoken = "9.2.0"
 # Performance measurements