Remove unnecessary dependencies.

Found by "cargo udeps"

Cargo.lock

@@ -546,12 +546,6 @@ dependencies = [
  "winapi",
 ]
 
-[[package]]
-name = "fs_extra"
-version = "1.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2022715d62ab30faffd124d40b76f4134a550a87792276512b18d63272333394"
-
 [[package]]
 name = "funty"
 version = "1.1.0"
@@ -1185,7 +1179,6 @@ dependencies = [
  "clap",
  "crc32c",
  "daemonize",
- "fs_extra",
  "futures",
  "hex",
  "humantime",
@@ -1199,21 +1192,17 @@ dependencies = [
  "rand",
  "regex",
  "routerify",
- "rust-s3",
  "scopeguard",
  "serde",
  "serde_json",
  "slog",
- "slog-async",
  "slog-scope",
  "slog-stdlog",
  "slog-term",
  "tar",
  "thiserror",
  "tokio",
- "tokio-stream",
  "toml",
- "walkdir",
  "workspace_hack",
  "zenith_metrics",
  "zenith_utils",

pageserver/Cargo.toml

@@ -17,30 +17,25 @@ futures = "0.3.13"
 hyper = "0.14"
 lazy_static = "1.4.0"
 slog-stdlog = "4.1.0"
-slog-async = "2.6.0"
 slog-scope = "4.4.0"
 slog-term = "2.8.0"
 slog = "2.7.0"
 log = "0.4.14"
 clap = "2.33.0"
 daemonize = "0.4.1"
-rust-s3 = { version = "0.27.0-rc4", features = ["no-verify-ssl"] }
 tokio = { version = "1.5.0", features = ["full"] }
-tokio-stream = { version = "0.1.5" }
 postgres-types = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
 postgres-protocol = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
 postgres = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
 routerify = "2"
 anyhow = "1.0"
 crc32c = "0.6.0"
-walkdir = "2"
 thiserror = "1.0"
 hex = { version = "0.4.3", features = ["serde"] }
 tar = "0.4.33"
 humantime = "2.1.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1"
-fs_extra = "1.2.0"
 toml = "0.5"
 scopeguard = "1.1.0"