Rust

Enable zend observer by default for PHP 8+ #477

Job	Run time
Fmt (ubuntu-24.04)	17s
Test (ubuntu-24.04, 8.1, 5.1.1)	8m 16s
Test (ubuntu-24.04, 7.4, 4.8.10)	7m 35s
Test (ubuntu-24.04, 7.3, 4.7.1)	6m 53s
Test (ubuntu-24.04, 8.4, 5.1.1)	6m 20s
Test (ubuntu-24.04, 8.0, 5.0.0)	7m 8s
Test (ubuntu-24.04, 8.2, 5.1.1)	7m 53s
Test (ubuntu-24.04, 8.3, 5.1.1)	8m 37s
Test (ubuntu-24.04, 8.2, 5.1.1, --features kafka-reporter)	8m 34s
Test (ubuntu-24.04, 7.2, 4.6.7)	6m 59s
Test (ubuntu-24.04, 8.5, 6.2.0)	7m 13s
required	2s
	1h 15m 47s

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