chore: fix error message

lib/oxrdf/src/cast_error.rs

@@ -1,11 +1,11 @@
 use std::error::Error;
 
-/// An error return if some content in the database is corrupted.
+/// An error return if trying to cast a term as something it cannot be converted to.
 #[derive(Debug, thiserror::Error)]
 #[error(transparent)]
 pub struct TermCastError(#[from] pub TermCastErrorKind);
 
-/// An error return if some content in the database is corrupted.
+/// An error return if trying to cast a term as something it cannot be converted to.
 #[derive(Debug, thiserror::Error)]
 pub enum TermCastErrorKind {
     #[error("{0}")]