Corrected to necessary pip requirements format
- [x] Addresses bug introduced by #22601

Requirements format for building pip env requires '==' instead of '='
Looks good to me, thanks
CC @gfyoung  That file is autogenerated. We need to update `scripts/convert_deps.py` to turn `=` into `==` for pip. And then run `scripts/convert_deps.py` to regenerate the file. Second what @TomAugspurger said above.  Good catch, @vadakattu ! @vadakattu do you have time to update this? I do. Back from vacation next week, will action.

- Krishna
On 25 Sep 2018, 18:35 +0200, Joris Van den Bossche <notifications@github.com>, wrote:
> @vadakattu do you have time to update this?
> —
> You are receiving this because you were mentioned.
> Reply to this email directly, view it on GitHub, or mute the thread.
 Seems to have been resolved in the meantime by #22889