build(deps): bump base64 from 0.13.1 to 0.21.0

Bumps [base64](https://github.com/marshallpierce/rust-base64) from 0.13.1 to 0.21.0.
- [Release notes](https://github.com/marshallpierce/rust-base64/releases)
- [Changelog](https://github.com/marshallpierce/rust-base64/blob/master/RELEASE-NOTES.md)
- [Commits](marshallpierce/rust-base64@v0.13.1...v0.21.0)

---
updated-dependencies:
- dependency-name: base64
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

integration/gcpkms/Cargo.toml

@@ -12,7 +12,7 @@ keywords = ["cryptography", "tink", "kms", "gcp"]
 categories = ["cryptography"]
 
 [dependencies]
-base64 = "^0.13"
+base64 = "^0.21"
 chrono = "^0.4"
 futures = "^0.3"
 http = "^0.2"

proto/Cargo.toml

@@ -17,7 +17,7 @@ default = []
 json = ["base64", "serde"]
 
 [dependencies]
-base64 = { version = "^0.13", optional = true }
+base64 = { version = "^0.21", optional = true }
 prost = "^0.11"
 serde = { version = "^1.0.147", features = ["derive"], optional = true }
 

tests/Cargo.toml

@@ -11,7 +11,7 @@ categories = ["cryptography"]
 publish = false
 
 [dependencies]
-base64 = "^0.13"
+base64 = "^0.21"
 ed25519-dalek = "^1.0.1"
 generic-array = "^0.14.6"
 hex = "^0.4.3"
@@ -29,7 +29,7 @@ tink-mac = "^0.2"
 tink-proto = "^0.2"
 
 [dev-dependencies]
-base64 = "^0.13"
+base64 = "^0.21"
 hex = "^0.4.3"
 lazy_static = "^1.4"
 maplit = "^1.0.2"