Fix error in core/Output.php for php8.0

Fix error in array_shift
array_map('array_shift', $this->headers) causes error as
array_shift(): Argument bcit-ci#1 ($array) must be passed by reference, value given

1 files changed, 6 insertions, 2 deletions

diff --git a/system/core/Output.php b/system/core/Output.php
index c56aff4b0..02c6d151b 100644
--- a/system/core/Output.php
+++ b/system/core/Output.php
@@ -300,9 +300,13 @@ class CI_Output {
 	public function get_header($header)
 	{
 		// Combine headers already sent with our batched headers
+		$headers = array();
+		foreach ($this->headers as $value)
+		{
+			$headers[] = $value[0];
+		}
 		$headers = array_merge(
-			// We only need [x][0] from our multi-dimensional array
-			array_map('array_shift', $this->headers),
+			$headers,
 			headers_list()
 		);