refactor(api, blocking)!: add generic Client trait, apply it to blocking

Author: oleonardolima

Cargo.toml

@@ -23,6 +23,7 @@ hex = { package = "hex-conservative", version = "0.2" }
 log = "^0.4"
 minreq = { version = "2.11.0", features = ["json-using-serde"], optional = true }
 reqwest = { version = "0.11", optional = true, default-features = false, features = ["json"] }
+serde_json = { version = "1.0.127" }
 
 [dev-dependencies]
 serde_json = "1.0"
@@ -31,7 +32,7 @@ electrsd = { version = "0.28.0", features = ["legacy", "esplora_a33e97e1", "bitc
 lazy_static = "1.4.0"
 
 [features]
-default = ["blocking", "async", "async-https"]
+default = ["blocking", "blocking-https", "async", "async-https"]
 blocking = ["minreq", "minreq/proxy"]
 blocking-https = ["blocking", "minreq/https"]
 blocking-https-rustls = ["blocking", "minreq/https-rustls"]