Bump format crates to latest prereleases (#539)

Bumps the following:
- pkcs1 v0.8.0-rc.3
- pkcs8 v.11.0-rc.6
- spki v0.8.0-rc.4

Author: tarcieri

Cargo.lock

@@ -23,11 +23,11 @@ subtle = { version = "2.6.1", default-features = false }
 zeroize = { version = "1.5", features = ["alloc"] }
 
 # optional dependencies
-pkcs1 = { version = "0.8.0-rc.2", optional = true, default-features = false, features = ["alloc", "pem"] }
-pkcs8 = { version = "0.11.0-rc.4", optional = true, default-features = false, features = ["alloc", "pem"] }
+pkcs1 = { version = "0.8.0-rc.3", optional = true, default-features = false, features = ["alloc", "pem"] }
+pkcs8 = { version = "0.11.0-rc.6", optional = true, default-features = false, features = ["alloc", "pem"] }
 serdect = { version = "0.3.0", optional = true }
 sha1 = { version = "0.11.0-rc.0", optional = true, default-features = false, features = ["oid"] }
-spki = { version = "0.8.0-rc.2", optional = true, default-features = false, features = ["alloc"] }
+spki = { version = "0.8.0-rc.4", optional = true, default-features = false, features = ["alloc"] }
 sha2 = { version = "0.11.0-rc.0", optional = true, default-features = false, features = ["oid"] }
 serde = { version = "1.0.184", optional = true, default-features = false, features = ["derive"] }
 
@@ -68,6 +68,3 @@ opt-level = 2
 
 [profile.bench]
 debug = true
-
-[patch.crates-io]
-pkcs1 = { git = "https://github.com/RustCrypto/formats/" }