refactor: remove stripe webhook flow for free product

Cargo.lock

@@ -72,15 +72,12 @@ dependencies = [
  "axum",
  "chrono",
  "fastrand",
- "hex",
- "hmac",
  "jsonwebtoken",
  "metrics",
  "metrics-exporter-prometheus",
  "redis",
  "serde",
  "serde_json",
- "sha2",
  "tokio",
  "tokio-postgres",
  "tracing",
@@ -577,12 +574,6 @@ version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 
-[[package]]
-name = "hex"
-version = "0.4.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
-
 [[package]]
 name = "hmac"
 version = "0.12.1"