send notifications on upvote, new answer and correct answer

[joacoalvarez]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 16.82243% with 89 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
internal/utils/notifications/push.go	0.00%	56 Missing ⚠️
internal/services/answers/answer.go	39.39%	15 Missing and 5 partials ⚠️
internal/services/questions/question.go	35.71%	6 Missing and 3 partials ⚠️
internal/router/answer_router.go	0.00%	2 Missing ⚠️
internal/router/question_router.go	0.00%	2 Missing ⚠️

📢 Thoughts on this report? Let us know!