Refactor CAggTimeBucketInfo to remove redundancy

Inside `CAggTimebucketInfo` data structure we're using several
properties that actually is also part of `ContinuousAggsBucketFunction`,
so refactor the code to use it and remove the properties redundancy.

src/ts_catalog/continuous_agg.h

@@ -86,6 +86,7 @@ typedef struct ContinuousAggsBucketFunction
 	 * situations since PostgreSQL protects the bucket_function from deletion until the CAgg is
 	 * defined. */
 	Oid bucket_function;
+	Oid bucket_width_type; /* type of bucket_width */
 
 	/* Is the interval of the bucket fixed? */
 	bool bucket_fixed_interval;
@@ -147,15 +148,6 @@ typedef enum ContinuousAggHypertableStatus
 	HypertableIsMaterializationAndRaw = HypertableIsMaterialization | HypertableIsRawTable,
 } ContinuousAggHypertableStatus;
 
-typedef struct ContinuousAggMatOptions
-{
-	bool verbose;
-	bool within_single_transaction;
-	bool process_only_invalidation;
-	int64 invalidate_prior_to_time; /* exclusive, if not bucketed, the last invalidation bucket will
-									   cover this point */
-} ContinuousAggMatOptions;
-
 typedef struct CaggsInfoData
 {
 	/* (int32) elements */