Fix large-dates ambiguity by creating a repr:four modifier #1732

Job	Run time
Test (miri)	16m 57s
Type checking (MSRV, no_std)	2m 2s
Type-check benchmarks	18s
Type checking (MSRV, std_no_offset)	3m 35s
Test (Ubuntu, MSRV)	1m 51s
Type checking (MSRV, std_with_offset)	2m 29s
Test (Windows, MSRV)	2m 46s
Type checking (stable, no_std)	54s
Clippy	58s
Test (MacOS, MSRV)	1m 27s
Type checking (stable, std_no_offset)	2m 14s
Test (Ubuntu, stable)	46s
Type checking (stable, std_with_offset)	1m 27s
Test (Windows, stable)	1m 58s
Cross-build	31s
Test (MacOS, stable)	38s
Documentation	15s
Formatting	11s
Coverage	36s
Publish docs	0s
	41m 53s

Provide feedback