"holy spirit," being in the neuter gender in NT Greek, is properly referred to with neuter pronouns ("it," "itself," etc.).
The Encyclopedia Americana tells us:
“The doctrine of the Holy Spirit [as a person who is God] is a distinctly Christian one.... the Spirit of Jehovah [in the OT] is the active divine principle in nature. .... But it is in the New Testament [NT] that we find the bases of the doctrine of the Spirit’s personality.” And “Yet the early Church did not forthwith attain to a complete doctrine; nor was it, in fact, until after the essential divinity of Jesus had received full ecclesiastical sanction [in 325 A.D. at the Council of Nicea] that the personality of the Spirit was explicitly recognized, and the doctrine of the Trinity formulated [381 A.D.].” Also, “It is better to regard the Spirit as the agency which, proceeding from the Father and the Son, dwells in the church as the witness and power of the life therein.” - v. 14, p. 326, 1957.
Many historians and Bible scholars (many of them trinitarians) freely admit the above truth. For example:
“On the whole, the New Testament, like the Old, speaks of the Spirit as a divine energy or power.” - A Catholic Dictionary.
“The majority of NT texts reveal God’s spirit as something, not someone” - New Catholic Encyclopedia, p. 575, Vol. 13, 1967.
“It is important to realize that for the first Christians the Spirit was thought of in terms of divine power.” - New Bible Dictionary, p. 1139, Tyndale House Publishers, 1984.
“The emergence of Trinitarian speculations in early church theology led to great difficulties in the article about the Holy Spirit. For the being-as-person of the Holy Spirit, which is evident in the New Testament as divine power...could not be clearly grasped.... The Holy Spirit was viewed not as a personal figure but rather as a power” - The New Encyclopedia Britannica.
“The true divinity of the third person [the holy spirit] was asserted...finally by the Council of Constantinople of 381 A. D.” - A Catholic Dictionary.
Yes, the Council of Constantinople (381 A. D.) first officially decreed “the personality of the Holy Spirit”. - Cairns, pp. 142, 145; also see Encyclopedia Britannica, v. 6, p. 22, 1985 ed.