Does anyone maybe have a reference to the proof of the following result by Tate?

Let $\Gamma$ be the absolute Galois group of the rationals. Then the second cohomology group (for trivial $\Gamma$-action) H$^2(\Gamma, \mathbb{Q}/\mathbb{Z})$ is trivial.

Unfortunately I couldn't find it online or in the library. Any help would be greatly appreciated!

Kind regards!