docs: add changelog and upgrade for v4.7.3 (#10068) #14556

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.3) / Sanity Tests	3m 7s
Others (8.2) / Sanity Tests	4m 0s
Others (8.5) / Sanity Tests	2m 51s
Others (8.4) / Sanity Tests	3m 12s
CacheLive (8.2) / Cache Live Tests	2m 28s
CacheLive (8.5) / Cache Live Tests	2m 16s
SeparateProcess (8.2) / tests	3m 32s
CacheLive (8.4) / Cache Live Tests	2m 17s
SeparateProcess (8.3) / tests	3m 32s
CacheLive (8.3) / Cache Live Tests	2m 21s
DatabaseLive (8.2, MySQLi, 5.7) / tests	3m 43s
SeparateProcess (8.5) / tests	3m 40s
DatabaseLive (8.3, Postgre, 8.0) / tests	3m 12s
SeparateProcess (8.4) / tests	3m 26s
DatabaseLive (8.2, OCI8, 8.0) / tests	8m 0s
DatabaseLive (8.3, OCI8, 8.0) / tests	7m 24s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 59s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 20s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 25s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	5m 44s
DatabaseLive (8.2, MySQLi, 8.0) / tests	4m 50s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	6m 18s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 23s
DatabaseLive (8.5, Postgre, 8.0) / tests	2m 50s
DatabaseLive (8.5, SQLite3, 8.0) / tests	2m 25s
DatabaseLive (8.5, MySQLi, 8.0) / tests	5m 16s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 59s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 22s
DatabaseLive (8.4, MySQLi, 8.0) / tests	4m 44s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 42s
DatabaseLive (8.5, OCI8, 8.0) / tests	7m 5s
DatabaseLive (8.3, MySQLi, 8.0) / tests	5m 37s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 52s
Upload coverage results to Coveralls / coveralls	46s
	2h 17m 40s

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