tflint: add withPlugins passthru

This can be used to build a tflint with plugins like this:

```
tflint.withPlugins (cp: [ cp.tflint-ruleset-aws ])
```

pkgs/development/tools/analysis/tflint/default.nix

@@ -1,4 +1,12 @@
-{ lib, buildGoModule, fetchFromGitHub }:
+{ lib
+, buildGoModule
+, fetchFromGitHub
+, runCommand
+, makeWrapper
+, tflint
+, tflint-plugins
+, symlinkJoin
+}:
 
 buildGoModule rec {
   pname = "tflint";
@@ -19,6 +27,22 @@ buildGoModule rec {
 
   ldflags = [ "-s" "-w" ];
 
+  passthru.withPlugins = plugins:
+    let
+      actualPlugins = plugins tflint-plugins;
+      pluginDir = symlinkJoin {
+        name = "tflint-plugin-dir";
+        paths = [ actualPlugins ];
+      };
+    in
+    runCommand "tflint-with-plugins"
+      {
+        nativeBuildInputs = [ makeWrapper ];
+      } ''
+      makeWrapper ${tflint}/bin/tflint $out/bin/tflint \
+        --set TFLINT_PLUGIN_DIR "${pluginDir}"
+    '';
+
   meta = with lib; {
     description = "Terraform linter focused on possible errors, best practices, and so on";
     homepage = "https://github.com/terraform-linters/tflint";