test: add helpers for creating P2TR scripts/addresses from output key

test/functional/test_framework/script_util.py

@@ -105,6 +105,11 @@ def script_to_p2sh_p2wsh_script(script):
     return script_to_p2sh_script(p2shscript)
 
 
+def output_key_to_p2tr_script(key):
+    assert len(key) == 32
+    return program_to_witness_script(1, key)
+
+
 def check_key(key):
     if isinstance(key, str):
         key = bytes.fromhex(key)  # Assuming this is hex string