Improve valid range handling: Part 1

[bena-nasa]

This is the first of multiple parts to deal with handling cases in ExtData when you are on a system that does not have all the data that is implied by the valid range. @mathomp4 hit this with his tiny BC's on bucy.

This is a few common sense fixes as follows

1. In the multi-rule case I was checking the collection metadata for each item in the rule. This is what was causing the issue with small BC's. But if the actual job execution does not even overlap the range of for one of the rules in an item this is just not necessary. So I get the range of the run from the clock and only do this introspection if the run range overlaps the use this rule range.
2. When I do go to try to find a file to get the metadata, rather than starting at the first valid range, I changed the code to use the current time. Only if a file is not found do I use the valid range to try to find any file. This also was causing a problem with tiny BC's on bucy.

Note that I will make a similar change in ExtData in MAPL3 as it has the same issue.

Types of change(s)

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Trivial change (affects only documentation or cleanup)
• Refactor (no functional changes, no api changes)

Checklist

• Tested this change with a run of GEOSgcm
• Ran the Unit Tests (make tests)

Description

Related Issue