Update babel monorepo to v7.23.9 #2079

Job	Run time
Static analysis	1m 2s
Dependencies, Unit tests (16)	1m 29s
Dependencies, Unit tests (18)	1m 24s
Dependencies, Unit tests (20)	1m 27s
Build application (govuk-docs)	2m 10s
Build application (govuk-template)	1m 32s
Build libraries	1m 53s
Test application (govuk-docs, chromium)	1m 33s
Test application (govuk-docs, firefox)	1m 43s
Test application (govuk-docs, electron)	1m 15s
Test application (govuk-template, chromium)	1m 20s
Test application (govuk-template, firefox)	1m 44s
Test application (govuk-template, electron)	1m 15s
	19m 47s

Provide feedback