Finished the dark theme

...nt/src/components/forms/AssigneesForm/assignees-form.scss

client/src/components/forms/AssigneesForm/index.tsx

.../components/forms/RequirementsForm/requirements-form.scss

client/src/components/forms/TaskForm/task-form.scss

client/src/components/forms/UserForm/user-form.scss

client/src/components/forms/form.scss

...components/graphs/CircularProgress/circular-progress.scss

...src/components/graphs/LinearProgress/linear-progress.scss

client/src/components/helpers/Filter/filter.scss

client/src/components/layout/CommentList/comment-list.scss

client/src/components/navigation/Sidebar/index.tsx

client/src/components/ui/Avatar/avatar.scss

client/src/components/ui/Comment/comment.scss

client/src/components/ui/LongText/markdown.scss

client/src/components/ui/Popup/popup.scss

client/src/components/ui/TextInput/text-input.scss

client/src/components/ui/TimeInput/index.tsx

client/src/components/ui/TimeInput/time-input.scss

client/src/index.tsx

client/src/pages/Home/home.scss