Don't persist BFT proposed blocks, only committed ones

Signed-off-by: Matthew Whitehead <matthew1001@gmail.com>

Author: matthew1001

consensus/qbft/src/main/java/org/hyperledger/besu/consensus/qbft/validation/ProposalPayloadValidator.java

@@ -150,7 +150,7 @@ private boolean validateBlock(final Block block) {
 
     final var validationResult =
         blockValidator.validateAndProcessBlock(
-            protocolContext, block, HeaderValidationMode.LIGHT, HeaderValidationMode.FULL);
+            protocolContext, block, HeaderValidationMode.LIGHT, HeaderValidationMode.FULL, false);
 
     if (!validationResult.isSuccessful()) {
       LOG.info(