Is saying "None has the right to be worshipped but Allah alone, Who has no partner; to Him belongs all sovereignty and all praise, and He is over all things competent" 100 times daily after the Fajr and Asr prayers desirable, or is it considered an innovation?

The Sunnah emphasizes reciting the remembrance (dhikr) "Lā ilāha illā Allāh, waḥdahu lā sharīka lahu, lahu al-mulku wa lahu al-ḥamdu, wa huwa ‘alā kulli shay’in qadīr" (There is no god but Allah, alone without partner. To Him belongs all sovereignty and praise, and He is over all things competent) one hundred times daily, with an indication that it is best to recite it consecutively at the beginning of the day. It is also established to recite this dhikr one hundred times in the morning and evening, or ten times in the morning and ten times in the evening, and all of this is good and legislated. Increasing beyond that is permissible and recommended.