`assert()` for maximum limit on number of filters in pipeline is off by 1

The maximum number of filters that can be added to a filter pipeline is documented as 32 (`H5Z_MAX_NFILTERS`). The `assert()` in `H5Z_pipeline()` currently checks that the number of filters in a pipeline is less than OR equal to this number, causing a filter pipeline with 32 filters in it to result in a crash for debug builds. This should be updated to allow the documented number of filters and a test should be added.