Fixes #2337: External encryption method (#2367)

Signed-off-by: AbstractionFactory <179820029+abstractionfactory@users.noreply.github.com>

website/docs/language/state/examples/encryption/external-method/method-external.tofu

@@ -0,0 +1,10 @@
+terraform {
+  encryption {
+    key_provider "external" "foo" {
+      encrypt_command = ["./some_program", "--encrypt"]
+      decrypt_command = ["./some_program", "--decrypt"]
+      # Optional:
+      keys = key_provider.some.provider
+    }
+  }
+}