sqlite: add `nixpkgs-update: no auto update` for the update bot

the version assert for sqlite and sqldiff/sqlite-analyzer means that the PRs the bot submits are broken

pkgs/development/libraries/sqlite/default.nix

···
   pname = "sqlite";
   version = "3.37.2";
 
+  # nixpkgs-update: no auto update
   # NB! Make sure to update ./tools.nix src (in the same directory).
   src = fetchurl {
     url = "https://sqlite.org/2022/sqlite-autoconf-${archiveVersion version}.tar.gz";

pkgs/development/libraries/sqlite/tools.nix

···
     inherit pname;
     version = "3.37.2";
 
+    # nixpkgs-update: no auto update
     src = assert version == sqlite.version; fetchurl {
       url = "https://sqlite.org/2022/sqlite-src-${archiveVersion version}.zip";
       sha256 = "sha256-SGdwtNX4i1uw26VA3W7hdjBn11Od/uGKfGb+m7A9Ftk=";