fix(files_sharing): validate input in PublicPreviewController#getPreview #5514

Job	Run time
gate	10s
Playwright setup	3m 3s
Playwright tests for installer	12m 34s
Playwright tests 8 / 8	15m 47s
Playwright tests 7 / 8	12m 50s
Playwright tests 1 / 8	15m 29s
Playwright tests 5 / 8	16m 19s
Playwright tests 2 / 8	15m 0s
Playwright tests 6 / 8	13m 24s
Playwright tests 4 / 8	13m 29s
Playwright tests 3 / 8	14m 10s
merge-reports	1m 22s
playwright-test-summary	6s
	2h 13m 43s

Navigation Menu