Can anyone advise if in any scripture it is mentioned that Astral projection is evil?
Doing things not sanctioned by shastras is a recipe for trouble. Please consider Bhagavan Krishna's advice from Bhagavad Gita
yaḥ śāstra-vidhim utsṛjya vartate kāma-kārataḥ
na sa siddhim avāpnoti na sukhaṁ na parāṁ gatim
He who discards scriptural injunctions and acts according to his own whims attains neither perfection, nor happiness, nor the supreme destination. [Bhagavad Gita 16.23]