docs: add changelog and upgrade for v4.7.3 #14555

Job	Run time
Setup PHP Version for Code Coverage	4s
Others (8.3) / Sanity Tests	3m 0s
Others (8.4) / Sanity Tests	2m 45s
Others (8.2) / Sanity Tests	3m 47s
Others (8.5) / Sanity Tests	2m 45s
CacheLive (8.3) / Cache Live Tests	2m 19s
CacheLive (8.2) / Cache Live Tests	2m 50s
SeparateProcess (8.4) / tests	3m 42s
SeparateProcess (8.2) / tests	3m 37s
CacheLive (8.5) / Cache Live Tests	2m 23s
CacheLive (8.4) / Cache Live Tests	2m 16s
SeparateProcess (8.5) / tests	3m 47s
SeparateProcess (8.3) / tests	3m 30s
DatabaseLive (8.4, MySQLi, 8.0) / tests	4m 39s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 53s
DatabaseLive (8.5, MySQLi, 8.0) / tests	4m 41s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 21s
DatabaseLive (8.5, Postgre, 8.0) / tests	2m 46s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 53s
DatabaseLive (8.3, OCI8, 8.0) / tests	7m 16s
DatabaseLive (8.2, MySQLi, 5.7) / tests	4m 9s
DatabaseLive (8.3, Postgre, 8.0) / tests	3m 5s
DatabaseLive (8.4, Postgre, 8.0) / tests	3m 2s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 58s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 20s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 5s
DatabaseLive (8.5, SQLite3, 8.0) / tests	2m 2s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 58s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	7m 36s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	5m 43s
DatabaseLive (8.5, OCI8, 8.0) / tests	6m 35s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 31s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 49s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 58s
Upload coverage results to Coveralls / coveralls	41s
	2h 17m 46s

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