Vultr DNS: fix "grep: repetition-operator operand invalid" on FreeBSD

[skyksandr]

Part 1

@mjkrg reports here #2374 integration is no longer working on FreeBSD.
This PR aims to fix it.

On line 119, containing the command grep '^\{.*\}', on FreeBSD it needs an -E option to be able to parse the extended regular expression otherwise it chokes with the error message: "grep: repetition-operator operand invalid".

Part 2

The | tr -d '"' added to fix following error on cleanup stage:

Please refer to https://curl.haxx.se/libcurl/c/libcurl-errors.html for error code: 22
Error domains/skyder.by/records/"6d139034-bbfb-407d-bdf8-1619cfca45c8"
{"error":"resource ID cannot contain special characters","status":400}

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[Neilpang]

https://github.com/skyksandr/acme.sh/actions/runs/2916012688

[skyksandr]

@Neilpang Here is CI run after rebasing on current master:
https://github.com/skyksandr/acme.sh/actions/runs/4081483447