remove unused backends

they have been disabled for a long time, and are unlikely to ever make a comeback

Cargo.lock

@@ -514,7 +514,6 @@ dependencies = [
  "opentelemetry-otlp",
  "opentelemetry_sdk",
  "parking_lot",
- "persy",
  "rand",
  "regex",
  "reqwest",
@@ -587,21 +586,6 @@ dependencies = [
  "libc",
 ]
 
-[[package]]
-name = "crc"
-version = "3.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "69e6e4d7b33a94f0991c26729976b10ebde1d34c3ee82408fb536164fa10d636"
-dependencies = [
- "crc-catalog",
-]
-
-[[package]]
-name = "crc-catalog"
-version = "2.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "19d374276b40fb8bbdee95aef7c7fa6b5316ec764510eb64b8dd0e2ed0d7e7f5"
-
 [[package]]
 name = "crc32fast"
 version = "1.4.2"
@@ -842,16 +826,6 @@ dependencies = [
  "percent-encoding",
 ]
 
-[[package]]
-name = "fs2"
-version = "0.4.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9564fc758e15025b46aa6643b1b77d047d1a56a1aea6e01002ac0c7026876213"
-dependencies = [
- "libc",
- "winapi",
-]
-
 [[package]]
 name = "futures-channel"
 version = "0.3.30"
@@ -1904,22 +1878,6 @@ version = "2.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e3148f5046208a5d56bcfc03053e3ca6334e51da8dfb19b6cdc8b306fae3283e"
 
-[[package]]
-name = "persy"
-version = "1.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9ef4b7250ab3a90ded0e284b2633469c23ef01ea868fe7cbb64e2f0a7d6f6d02"
-dependencies = [
- "crc",
- "data-encoding",
- "fs2",
- "linked-hash-map",
- "rand",
- "thiserror",
- "unsigned-varint",
- "zigzag",
-]
-
 [[package]]
 name = "pin-project"
 version = "1.1.5"
@@ -3395,12 +3353,6 @@ version = "0.2.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "673aac59facbab8a9007c7f6108d11f63b603f7cabff99fabf650fea5c32b861"
 
-[[package]]
-name = "unsigned-varint"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eb066959b24b5196ae73cb057f45598450d2c5f71460e98c49b738086eff9c06"
-
 [[package]]
 name = "untrusted"
 version = "0.9.0"
@@ -3802,15 +3754,6 @@ version = "1.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ced3678a2879b30306d323f4542626697a464a97c0a07c9aebf7ebca65cd4dde"
 
-[[package]]
-name = "zigzag"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70b40401a28d86ce16a330b863b86fd7dbee4d7c940587ab09ab8c019f9e3fdf"
-dependencies = [
- "num-traits",
-]
-
 [[package]]
 name = "zstd-sys"
 version = "2.0.10+zstd.1.5.6"