Fix (docs): grammar issue in the opening comment (#9012)

Author: 0xminds

crates/cairo-lang-sierra-to-casm/src/invocations/misc.rs

@@ -16,7 +16,7 @@ use crate::invocations::{BuiltinInfo, CostValidationInfo, add_input_variables};
 use crate::references::ReferenceExpression;
 use crate::relocations::{InstructionsWithRelocations, Relocation, RelocationEntry};
 
-/// Handles a revoke/enable/disable ap tracking instructions.
+/// Handles revoke/enable/disable AP-tracking instructions.
 pub fn build_update_ap_tracking(
     builder: CompiledInvocationBuilder<'_>,
 ) -> Result<CompiledInvocation, InvocationError> {