Factor vergen stuff to a build-info crate

build-info/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "build-info"
+version.workspace = true
+authors.workspace = true
+description.workspace = true
+homepage.workspace = true
+readme.workspace = true
+edition.workspace = true
+license.workspace = true
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+time = { version = "0.3.34", features = ["parsing"] }
+
+[build-dependencies]
+anyhow = "1.0.80"
+vergen-git2 = "1.0.0-beta.2"