fix: replace usage of RangeProof MR with Witness MR (#3129)

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## Description
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There are still some names references a rangeproof Mr, this does not exist anymore and there is only a witness Mr. 

## Motivation and Context
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## How Has This Been Tested?
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## Checklist:
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* [x] I'm merging against the `development` branch.
* [x] I have squashed my commits into a single commit.

base_layer/core/src/blocks/block_header.rs

@@ -283,7 +283,7 @@ impl Display for BlockHeader {
         )?;
         writeln!(
             fmt,
-            "Merkle roots:\nInputs: {},\n Outputs: {} ({})\nRange proofs: {}\nKernels: {} ({})\n",
+            "Merkle roots:\nInputs: {},\n Outputs: {} ({})\nWitness: {}\nKernels: {} ({})\n",
             self.input_mr.to_hex(),
             self.output_mr.to_hex(),
             self.output_mmr_size,

base_layer/core/src/validation/block_validators.rs

@@ -275,7 +275,7 @@ fn check_mmr_roots<B: BlockchainBackend>(block: &Block, db: &B) -> Result<(), Va
     if header.witness_mr != mmr_roots.witness_mr {
         warn!(
             target: LOG_TARGET,
-            "Block header range_proof MMR roots in {} do not match calculated roots",
+            "Block header witness MMR roots in {} do not match calculated roots",
             block.hash().to_hex()
         );
         return Err(ValidationError::BlockError(BlockValidationError::MismatchedMmrRoots));

base_layer/core/src/validation/error.rs

@@ -53,14 +53,6 @@ pub enum ValidationError {
     ContainsSTxO,
     #[error("Transaction contains already outputs that already exist")]
     ContainsTxO,
-    #[error("The recorded chain accumulated difficulty was stronger")]
-    WeakerAccumulatedDifficulty,
-    #[error("Invalid output merkle root")]
-    InvalidOutputMr,
-    #[error("Invalid kernel merkle root")]
-    InvalidKernelMr,
-    #[error("Invalid range proof merkle root")]
-    InvalidRangeProofMr,
     #[error("Final state validation failed: The UTXO set did not balance with the expected emission at height {0}")]
     ChainBalanceValidationFailed(u64),
     #[error("Proof of work error: {0}")]