fix: bump bigdecimal version to 0.4.5 (#15)

# Rationale for this change
Our dependency, `bigdecimal`, restricted `num-bigint` version in 0.4.4,
leading to `num-bigint` downgrade to 0.3.3 which caused CI issues for
us. Since [the
issue](akubera/bigdecimal-rs#128) has been
resolved we need to bump our `bigdecimal` version to 0.4.5.
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# What changes are included in this PR?
- Bump `bigdecimal` version to 0.4.5
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# Are these changes tested?
Yes
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Cargo.toml

@@ -21,7 +21,7 @@ arrayvec = { version = "0.7" }
 arrow = { version = "45.0" }
 arrow-csv = { version = "45.0" }
 bit-iter = { version = "1.1.1" }
-bigdecimal = { version = "0.4.3", features = ["serde"] }
+bigdecimal = { version = "0.4.5", features = ["serde"] }
 blake3 = { version = "1.3.3" }
 blitzar = { version = "3.0.1" }
 bumpalo = { version = "3.11.0" }