PHPStan: correct /includes/acf-input-functions.php

[kraftbj]

message: '#^Function acf_checkbox_input\(\) should return string but return statement is missing\.$#'
			identifier: return.missing
			count: 1
			path: ../includes/acf-input-functions.php

		-
			message: '#^Function acf_file_input\(\) should return string but return statement is missing\.$#'
			identifier: return.missing
			count: 1
			path: ../includes/acf-input-functions.php

		-
			message: '#^Function acf_hidden_input\(\) should return string but return statement is missing\.$#'
			identifier: return.missing
			count: 1
			path: ../includes/acf-input-functions.php

		-
			message: '#^Function acf_radio_input\(\) should return string but return statement is missing\.$#'
			identifier: return.missing
			count: 1
			path: ../includes/acf-input-functions.php

		-
			message: '#^Function acf_select_input\(\) should return string but return statement is missing\.$#'
			identifier: return.missing
			count: 1
			path: ../includes/acf-input-functions.php

		-
			message: '#^Function acf_text_input\(\) should return string but return statement is missing\.$#'
			identifier: return.missing
			count: 1
			path: ../includes/acf-input-functions.php

		-
			message: '#^Function acf_textarea_input\(\) should return string but return statement is missing\.$#'
			identifier: return.missing
			count: 1
			path: ../includes/acf-input-functions.php