add prettier for auto formatting (#231)

* [Prettier] Add "prettier"

Makes the formatting of the code consistent.
By using the eslint-plugin-prettier formatting issues will be highlighted as a lint error.
These errors will be auto fixed by running "lint --fix" (which can be done automatically on file save)

* [Prettier] Add "prettier" - Fix formatting

src/components/source/SourceMangaGrid.tsx

@@ -17,8 +17,14 @@ function filterManga(mangas: IMangaCard[]): IMangaCard[] {
 
 export default function SourceMangaGrid(props: IMangaGridProps) {
     const {
-        mangas, isLoading, hasNextPage, lastPageNum,
-        setLastPageNum, message, messageExtra, gridLayout,
+        mangas,
+        isLoading,
+        hasNextPage,
+        lastPageNum,
+        setLastPageNum,
+        message,
+        messageExtra,
+        gridLayout,
     } = props;
 
     const filteredManga = filterManga(mangas);