docs(REVIEWS): point people to signup.tvl.fyi for account creation

Rather than invoking the old shell script, people can now use the web
UI to create the entry.

Change-Id: Ic1b065d219fde9977bb1d8ee59ce7ac5f27e2e29
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9306
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>

docs/REVIEWS.md

@@ -121,18 +121,7 @@ instance, follow these instructions:
 2. Clone the depot locally (via `git clone "https://cl.tvl.fyi/depot"`).
 3. Create a user entry in our LDAP server in [ops/users][ops-users].
 
-   We recommend using ARGON2 password hashes, which can be created
-   with the `slappasswd` tool if OpenLDAP was compiled with ARGON2
-   support.
-
-   For convenience, we provide a wrapper script for this that you can
-   build with `nix-build -A tools.hash-password` in a depot checkout.
-   Alternatively, if you have `direnv` installed, you can add the
-   depot to your allowlist and just run `hash-password` which should
-   be added to your `$PATH` by `direnv`.
-
-   You can probably create ARGON2 hashes with other tools, but that is
-   your job to figure out.
+   The entry can be generated using [//web/pwcrypt](https://signup.tvl.fyi/).
 4. Create a commit adding yourself (see e.g.
    [CL/2671](https://cl.tvl.fyi/c/depot/+/2671))
 5. Submit the commit via email (see below).

tools/hash-password.nix

@@ -1,5 +1,7 @@
 # Utility for invoking slappasswd with the correct options for
 # creating an ARGON2 password hash.
+#
+# Users should generally use https://signup.tvl.fyi instead.
 { pkgs, ... }:
 
 let