fix: removes docstring ref to default_value argument.

[thomasheartman]

Description

This argument was made obsolete a while ago and makes the client crash
when used.

Based on @sighphyre's comment in Unleash PR 1582.

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Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

This has not been tested yet. It seems like straight forward doc-update to me, but if there are ways to verify it, I'm more than happy to.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[coveralls]

Coverage remained the same at 96.159% when pulling af592d0 on fix/remove-obsolete-arg into 38959f9 on main.

[sighphyre]

Nice