refactor: improve cache control headers formatting (#4536)

Co-authored-by: Alexandr <qwerty541zxc@gmail.com>

backend/src/common/cache.js

@@ -31,7 +31,9 @@ const resolveCacheSeconds = ({ requested, def, min, max }) => {
 const setCacheHeaders = (res, cacheSeconds) => {
   res.setHeader(
     "Cache-Control",
-    `max-age=${cacheSeconds}, s-maxage=${cacheSeconds}, stale-while-revalidate=${CONSTANTS.ONE_DAY}`,
+    `max-age=${cacheSeconds}, ` +
+      `s-maxage=${cacheSeconds}, ` +
+      `stale-while-revalidate=${CONSTANTS.ONE_DAY}`,
   );
 };
 

backend/tests/gist.test.js

@@ -188,7 +188,9 @@ describe("Test /api/gist", () => {
     expect(res.setHeader).toBeCalledWith("Content-Type", "image/svg+xml");
     expect(res.setHeader).toBeCalledWith(
       "Cache-Control",
-      `max-age=${CONSTANTS.CARD_CACHE_SECONDS}, s-maxage=${CONSTANTS.CARD_CACHE_SECONDS}, stale-while-revalidate=${CONSTANTS.ONE_DAY}`,
+      `max-age=${CONSTANTS.CARD_CACHE_SECONDS}, ` +
+        `s-maxage=${CONSTANTS.CARD_CACHE_SECONDS}, ` +
+        `stale-while-revalidate=${CONSTANTS.ONE_DAY}`,
     );
   });
 });