fix(terraphim_update): use hex::encode for sha2 0.11 output

sha2 0.11's finalize() output no longer implements LowerHex via the
format! macro. Add hex crate and encode the digest explicitly.

Refs #911

Author: Test User

Cargo.lock

@@ -29,6 +29,7 @@ chrono = { workspace = true }
 
 semver = "1.0"
 sha2 = "0.11"
+hex = "0.4"
 ureq = "2.9"
 dirs = "5.0"
 dialoguer = "0.12"

crates/terraphim_update/Cargo.toml

@@ -47,7 +47,7 @@ impl Backup {
         let mut hasher = Sha256::new();
         hasher.update(&contents);
         let result = hasher.finalize();
-        Ok(format!("{:x}", result))
+        Ok(hex::encode(result))
     }
 
     /// Verify that the backup file is intact
@@ -185,7 +185,7 @@ impl BackupManager {
         let mut hasher = Sha256::new();
         hasher.update(&contents);
         let result = hasher.finalize();
-        Ok(format!("{:x}", result))
+        Ok(hex::encode(result))
     }
 
     /// Rotate backups to maintain the maximum count