Remove sponsorship reference in heap optimizations post

V8 team is not sponsored. Work is actually done by engineers of
different companies. Rewrite the credits section accordingly.

src/blog/speeding-up-v8-heap-snapshots.md

@@ -156,4 +156,4 @@ Finally, now that we improved the generation phase, the biggest cost is now the
 
 ## Credits
 
-This work was possible thanks to the sponsorship of [Igalia](https://www.igalia.com) and [Bloomberg](https://techatbloomberg.com).
+This was possible thanks to the work of [Igalia](https://www.igalia.com) and [Bloomberg](https://techatbloomberg.com) engineers.