update_substrate_template doesn't replace dependency references correctly

[joao-paulo-parity]

As demonstrated by https://github.com/substrate-developer-hub/substrate-parachain-template/pull/149/files and pointed out by https://github.com/substrate-developer-hub/substrate-parachain-template/pull/149#pullrequestreview-1271942422, the update_substrate_template script seems to incorrectly replace branch = with " branch" =. There might be other issues, but this is the obvious one.

[joao-paulo-parity]

Apparently caused by a problem in Diener which was fixed in paritytech/diener@0e35ce7. Perhaps the problem will go away if we were to update Diener.