fixes after the review

Author: iakovenkos

barretenberg/cpp/src/barretenberg/stdlib/encryption/schnorr/schnorr.test.cpp

@@ -123,7 +123,7 @@ TEST(stdlib_schnorr, schnorr_signature_verification_result)
     stdlib::schnorr_signature_bits sig = stdlib::schnorr_convert_signature(&builder, signature);
     byte_array_ct message(&builder, longer_string);
     bool_ct signature_result = schnorr_signature_verification_result(message, pub_key, sig);
-    EXPECT_EQ(signature_result.get_normalized_witness_index(), true);
+    EXPECT_EQ(signature_result.get_value(), true);
 
     info("num gates = ", builder.get_estimated_num_finalized_gates());
 

barretenberg/cpp/src/barretenberg/stdlib/primitives/bool/bool.cpp

@@ -89,10 +89,10 @@ bool_t<Builder> bool_t<Builder>::from_witness_index_unsafe(Builder* ctx, const u
     ASSERT(witness_index != IS_CONSTANT);
     bool_t<Builder> result(ctx);
     result.witness_index = witness_index;
-    bb::fr value = ctx->get_variable(witness_index);
+    const bb::fr value = ctx->get_variable(witness_index);
     // It does not create a constraint.
     BB_ASSERT_EQ(value * value - value, 0, "bool_t: creating a witness bool from a non-boolean value");
-    result.witness_bool = (ctx->get_variable(witness_index) == 1);
+    result.witness_bool = (value == 1);
     result.witness_inverted = false;
     return result;
 }