Prevent password leakage via curl process information

[rrobgill]

What does this PR aim to accomplish?:

Prevent leakage of password via process information of curl command.

At the moment, even if the password is entered manually at startup

The password is visible in the process list when it is sent via the curl command
eg, as viewed in htop
Before:

How does this PR accomplish the above?:

Makes use of a heredoc to provide the json containing the password (and totp) to the curl command.

After:

Link documentation PRs if any are needed to support this PR:

N/A

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