fix: refine FormRequest JSON failure detection #15207

Job	Run time
Setup PHP Version for Code Coverage	3s
Others (8.4) / Sanity Tests	1m 51s
Others (8.3) / Sanity Tests	1m 34s
Others (8.2) / Sanity Tests	3m 8s
Others (8.5) / Sanity Tests	1m 32s
SeparateProcess (8.5) / tests	2m 12s
SeparateProcess (8.4) / tests	2m 1s
SeparateProcess (8.3) / tests	2m 38s
CacheLive (8.4) / Cache Live Tests	1m 28s
CacheLive (8.5) / Cache Live Tests	1m 26s
SeparateProcess (8.2) / tests	2m 10s
CacheLive (8.2) / Cache Live Tests	1m 44s
CacheLive (8.3) / Cache Live Tests	1m 34s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	6m 16s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 8s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 15s
DatabaseLive (8.5, Postgre, 8.0) / tests	1m 36s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 58s
DatabaseLive (8.3, SQLite3, 8.0) / tests	1m 18s
DatabaseLive (8.4, Postgre, 8.0) / tests	1m 52s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	5m 19s
DatabaseLive (8.4, SQLite3, 8.0) / tests	1m 7s
DatabaseLive (8.2, OCI8, 8.0) / tests	8m 50s
DatabaseLive (8.2, Postgre, 8.0) / tests	2m 50s
DatabaseLive (8.3, Postgre, 8.0) / tests	1m 42s
DatabaseLive (8.4, MySQLi, 8.0) / tests	3m 27s
DatabaseLive (8.3, MySQLi, 8.0) / tests	3m 35s
DatabaseLive (8.5, MySQLi, 8.0) / tests	4m 8s
DatabaseLive (8.3, OCI8, 8.0) / tests	7m 47s
DatabaseLive (8.2, MySQLi, 5.7) / tests	3m 10s
DatabaseLive (8.5, OCI8, 8.0) / tests	7m 46s
DatabaseLive (8.5, SQLite3, 8.0) / tests	1m 7s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 3s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 13s
Upload coverage results to Coveralls / coveralls	56s
	1h 51m 44s

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