fix: replace filter_input with sanitize_text_field

[jasonbahl]

What does this implement/fix? Explain your changes.

This replaces the filter_input function with sanitize_text_field when verifying the nonce for checking Admin Location Rules when ACF Field Group pages are loaded or various settings of the field group are modified.

The FILTER_SANITIZE_STRING argument was deprecated in php 8.1

Does this close any currently open issues?

closes #69

Any other comments?

With ACF Pro v6.1.7, WPGraphQL 1.14.9 and WPGraphQL for ACF (v2.0.0-beta.3.1.0) active, when opening the admin page for an ACF Field Group:

Before

The following error message would be displayed in the console in response to the AJAX method to check the graphql location rules:

After

The error message is no longer returned:

[coveralls]

Pull Request Test Coverage Report for Build 183f7c25f7a35f42abd202b4d012d146f3008edd-PR-73

• 0 of 1 (0.0%) changed or added relevant line in 1 file are covered.
• 49 unchanged lines in 1 file lost coverage.
• Overall coverage remained the same at 56.926%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/Admin/Settings.php	0	1	0.0%

Files with Coverage Reduction	New Missed Lines	%
src/Admin/Settings.php	49	0%

Totals
Change from base Build 6f81e4fdf3dce9bd0ef7c5c0299f240d8d96f157:	0.0%
Covered Lines:	1500
Relevant Lines:	2635

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💛 - Coveralls

[markkelnar]

👍