BREAKING(unstable): Use hosts for net allowlists (#8845)

Allowlist checking already uses hosts but for some reason 
requests, revokes and the runtime permissions API use URLs.

- BREAKING(lib.deno.unstable.d.ts): Change 
NetPermissionDescriptor::url to NetPermissionDescriptor::host

- fix(runtime/permissions): Don't add whole URLs to the 
allowlist on request

- fix(runtime/permissions): Harden strength semantics:
({ name: "net", host: "127.0.0.1" } is stronger than 
{ name: "net", host: "127.0.0.1:8000" }) for blocklisting

- refactor(runtime/permissions): Use tuples for hosts, make 
the host optional in Permissions::{query_net, request_net, revoke_net}()

std/permissions/mod.ts

@@ -14,8 +14,8 @@ function getPermissionString(descriptors: Deno.PermissionDescriptor[]): string {
                 ? `--allow-${pd.name}=${pd.path}`
                 : `--allow-${pd.name}`;
             case "net":
-              return pd.url
-                ? `--allow-${pd.name}=${pd.url}`
+              return pd.host
+                ? `--allow-${pd.name}=${pd.host}`
                 : `--allow-${pd.name}`;
             default:
               return `--allow-${pd.name}`;