fix: fix compile error using decimal-rs 0.1.42 (#5228)

Description
---
Fixes compile error caused by breaking change for decimal-rs >=0.1.42

Motivation and Context
---
decimal-rs removed the Error impl for their error type in 0.1.42 but released this breaking change as a patch.
The thiserror from impl requires that the Error trait be implemented so this PR manually implements From

~~Causing compile error in tari-project/tari-dan#421 worked around this and other issues by not updating all dependencies and locking to 0.47.0-pre.0 tag.

How Has This Been Tested?
---
Code compiles

<!-- Does this include a breaking change? If so, include this line as a footer -->
<!-- BREAKING CHANGE: Description what the user should do, e.g. delete a database, resync the chain -->

base_layer/core/Cargo.toml

@@ -44,7 +44,7 @@ chacha20poly1305 = "0.10.1"
 chrono = { version = "0.4.19", default-features = false, features = ["serde"] }
 criterion = { version = "0.4.0", optional = true  }
 croaring = { version = "0.5.2", optional = true }
-decimal-rs = "0.1.20"
+decimal-rs = "0.1.42"
 derivative = "2.2.0"
 digest = "0.9.0"
 fs2 = "0.4.0"

base_layer/core/src/transactions/tari_amount.rs

@@ -69,7 +69,14 @@ pub enum MicroTariError {
     #[error("Failed to parse value: {0}")]
     ParseError(String),
     #[error("Failed to convert value: {0}")]
-    ConversionError(#[from] DecimalConvertError),
+    ConversionError(DecimalConvertError),
+}
+
+// DecimalConvertError does not implement Error
+impl From<DecimalConvertError> for MicroTariError {
+    fn from(err: DecimalConvertError) -> Self {
+        MicroTariError::ConversionError(err)
+    }
 }
 /// A convenience constant that makes it easier to define Tari amounts.
 /// ```edition2018