sdk: Remove unused sha2 dependency.

Cargo.lock

@@ -1552,7 +1552,6 @@ dependencies = [
  "clap 4.3.19",
  "crypto_api_chachapoly",
  "darkfi-derive",
- "darkfi-derive-internal",
  "darkfi-sdk",
  "darkfi-serial",
  "dashu",
@@ -1721,7 +1720,6 @@ dependencies = [
  "pasta_curves",
  "rand 0.8.5",
  "rand_core 0.6.4",
- "sha2 0.10.7",
  "subtle",
  "thiserror",
 ]

Cargo.toml

@@ -97,7 +97,6 @@ dashu = {version = "0.3.1", optional = true}
 chrono = {version = "0.4.26", optional = true}
 darkfi-serial = {path = "src/serial", optional = true}
 darkfi-derive = {path = "src/serial/derive", optional = true}
-darkfi-derive-internal = {path = "src/serial/derive-internal", optional = true}
 itertools = {version = "0.11.0", optional = true}
 lazy_static = {version = "1.4.0", optional = true}
 # TODO: Test without serde

src/sdk/Cargo.toml

@@ -31,7 +31,6 @@ num-bigint = "0.4.3"
 num-traits = "0.2.16"
 pasta_curves = "0.5.1"
 rand_core = "0.6.4"
-sha2 = "0.10.7"
 
 # Misc
 lazy_static = "1.4.0"