disable the http/2 feature in rocket

nginx doesn't support proxying http/2 and this app is almost certainly
going to be put behind a reverse proxy. this also reduces the binary
size.

Cargo.lock

@@ -427,25 +427,6 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
 
-[[package]]
-name = "h2"
-version = "0.3.20"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97ec8491ebaf99c8eaa73058b045fe58073cd6be7f596ac993ced0b0a0c01049"
-dependencies = [
- "bytes",
- "fnv",
- "futures-core",
- "futures-sink",
- "futures-util",
- "http",
- "indexmap 1.9.3",
- "slab",
- "tokio",
- "tokio-util",
- "tracing",
-]
-
 [[package]]
 name = "hashbrown"
 version = "0.12.3"
@@ -526,7 +507,6 @@ dependencies = [
  "futures-channel",
  "futures-core",
  "futures-util",
- "h2",
  "http",
  "http-body",
  "httparse",
@@ -1397,7 +1377,6 @@ dependencies = [
  "futures-sink",
  "pin-project-lite",
  "tokio",
- "tracing",
 ]
 
 [[package]]

Cargo.toml

@@ -7,6 +7,7 @@ edition = "2021"
 
 [dependencies.rocket]
 version = "=0.5.0-rc.3"
+default_features = false
 features = ["json"]
 
 [dependencies.rust-embed]