Check for existing user downloads not working in all cases

[MattBlissett]

We have significant space used by duplicate user downloads, e.g.

• 0264549-230224095556074
• 0264553-230224095556074
• 0264554-230224095556074
• 0264567-230224095556074
• 0264573-230224095556074
• 0264574-230224095556074

With this code:

occurrence/occurrence-download-service/src/main/java/org/gbif/occurrence/download/resource/DownloadResource.java

Lines 386 to 399 in d8eaddc

	// Check for recent user downloads (of this same user) with the same predicate
	PagingResponse<Download> userDownloads =
	occurrenceDownloadService.listByUser(
	userAuthenticated.getName(),
	new PagingRequest(0, 50),
	EnumSet.of(PREPARING, RUNNING, SUCCEEDED));
	String existingUserDownload =
	matchExistingDownload(
	userDownloads,
	predicateDownloadRequest,
	Date.from(Instant.now().minus(4, ChronoUnit.HOURS)));
	if (existingUserDownload != null) {
	return existingUserDownload;
	}

the user should have been sent to 0264549-230224095556074 (the first download) for all subsequent requests.