taa_accept default to True when sign is True

Signed-off-by: Daniel Bluhm <daniel.bluhm@sovrin.org>

aries_cloudagent/ledger/indy.py

@@ -221,7 +221,7 @@ async def _submit(
         self,
         request_json: str,
         sign: bool = None,
-        taa_accept: bool = False,
+        taa_accept: bool = None,
         public_did: str = "",
     ) -> str:
         """
@@ -249,6 +249,9 @@ async def _submit(
         if public_did and sign is None:
             sign = True
 
+        if taa_accept is None and sign:
+            taa_accept = True
+
         if sign:
             if not public_did:
                 raise BadLedgerRequestError("Cannot sign request without a public DID")