Bump tagged-base64 from 0.3.4 to v0.4.0

Bumps [tagged-base64](https://github.com/EspressoSystems/tagged-base64) from 0.3.4 to v0.4.0.
- [Release notes](https://github.com/EspressoSystems/tagged-base64/releases)
- [Commits](EspressoSystems/tagged-base64@0.3.4...eb44914)

---
updated-dependencies:
- dependency-name: tagged-base64
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Cargo.toml

@@ -14,6 +14,6 @@ futures = "0.3"
 hotshot-types = { git = "https://github.com/EspressoSystems/hotshot-types", tag = "0.1.5" }
 serde = { version = "1.0", features = ["derive"] }
 snafu = { version = "0.7", features = ["backtraces"] }
-tagged-base64 = { git = "https://github.com/EspressoSystems/tagged-base64", tag = "0.3.4" }
+tagged-base64 = { git = "https://github.com/EspressoSystems/tagged-base64", tag = "v0.4.0" }
 tide-disco = { git = "https://github.com/EspressoSystems/tide-disco.git", tag = "v0.4.6" }
 toml = "0.8"