Add pods_shortcode_detect_from_current_post filter for more flexibility

[sc0ttkclark]

Description

This allows Pods to not rely as much on in_the_loop() so the shortcode can be used in more flexible ways. This is needed for pods-framework/pods-beaver-builder-themer-add-on#112

Changelog text for these changes

• Added: New filter pods_shortcode_detect_from_current_post allows you to override whether a shortcode should detect the post object outside of the loop (default is only when in_the_loop()).

PR Checklist

• My code is tested.
• My code follows the WordPress code style.
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