chore: extract TestEnv into separate crate

`TestEnv` is extracted into its own crate to serve as a framework
for testing other block explorer APIs.

crates/electrum/Cargo.toml

@@ -15,3 +15,8 @@ readme = "README.md"
 bdk_chain = { path = "../chain", version = "0.11.0", default-features = false }
 electrum-client = { version = "0.18" }
 #rustls = { version = "=0.21.1", optional = true, features = ["dangerous_configuration"] }
+
+[dev-dependencies]
+bdk_testenv = { path = "../testenv", default-features = false }
+electrsd = { version= "0.25.0", features = ["bitcoind_25_0", "esplora_a33e97e1", "legacy"] }
+anyhow = "1"

crates/electrum/src/electrum_ext.rs

@@ -189,7 +189,7 @@ impl<A: ElectrumApi> ElectrumExt for A {
     ) -> Result<(ElectrumUpdate, BTreeMap<K, u32>), Error> {
         let mut request_spks = keychain_spks
             .into_iter()
-            .map(|(k, s)| (k.clone(), s.into_iter()))
+            .map(|(k, s)| (k, s.into_iter()))
             .collect::<BTreeMap<K, _>>();
         let mut scanned_spks = BTreeMap::<(K, u32), (ScriptBuf, bool)>::new();