misc: replace manual From<T> for *Error with #[from]

This is a small simplification we can use since we use `thiserror`
anyway. Note that `#[from]` implies `#[source]` [0].

[0]: https://docs.rs/thiserror/2.0.12/thiserror/index.html

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com

performance-metrics/src/performance_tests.rs

@@ -25,17 +25,11 @@ enum Error {
     #[error("boot time could not be parsed")]
     BootTimeParse,
     #[error("infrastructure failure: {0}")]
-    Infra(#[source] InfraError),
+    Infra(#[from] InfraError),
     #[error("restore time could not be parsed")]
     RestoreTimeParse,
 }
 
-impl From<InfraError> for Error {
-    fn from(e: InfraError) -> Self {
-        Self::Infra(e)
-    }
-}
-
 const BLK_IO_TEST_IMG: &str = "/var/tmp/ch-blk-io-test.img";
 
 pub fn init_tests() {