Should I tell my neighbors and teach them about what I did previously, photographing them without their knowledge, even though I have repented from that action and disposed of all the photos?

What you did by violating the sanctity of your neighbors is a heinous sin. The Prophet, peace and blessings be upon him, said: "By Allah, he does not believe; by Allah, he does not believe; by Allah, he does not believe." It was asked, "Who, O Messenger of Allah?" He said, "He whose neighbor is not safe from his mischief." In a narration by Muslim: "He will not enter Paradise whose neighbor is not safe from his mischief." You must sincerely repent with remorse and a firm resolve not to return to it. Do not inform your neighbors of your sin, due to the evil that might result from it. Seeking forgiveness for them is sufficient for you.