[Process] Update process.rst

[matthewtrask]

This PR updates the text on the Process docs from "double brackets" which to a lot of people would mean [[]] to "double quotations" "" as demonstrated in the code example for the prepared statement.

[mattstauffer]

@matthewtrask Oops, I duplicated this; #14006

Yours is probably in the right branch, but mine has more changes. Would you mind reviewing mine and either adding my changes to your PR so I can close mine (assuming you got the right branch and I didn't) and then I can close mine? Thanks!

[matthewtrask]

@mattstauffer I looked to see if there was already a PR, I think we opened them at the same time :)

I brought your changes in here, which was better than what I added. I will default to the maintainers on which branch is better to keep open.

[javiereguiluz]

Matt (@matthewtrask), thanks a lot for this contribution! (and thanks to Matt (@mattstauffer) too for his contributions in the other pull request).

I'm sorry this fell off our radar and took us so long to merge. It's finally merged!

[matthewtrask]

@javiereguiluz its all good, thanks for the message :)