Don't reallocate buffers in fragment consolidation

[davisp]

Avoid needless buffer reallocations when consolidating fragments.

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TYPE: IMPROVEMENT
DESC: Avoid needless buffer reallocations when consolidating fragments.

[davisp]

Closing and re-opening from a different branch fro shortcut integration.

Apparently you can just tag a comment with the sc-##### in brackets and it links to the story.

[davisp]

[sc-36372]

[shortcut-integration]

This pull request has been linked to Shortcut Story #36372: create_buffers taking large percentage of time during consolidation.

[eric-hughes-tiledb]

I'm not convinced that calling resize is better than destroying and recreating the workspace. If the sizes don't change (maybe for shortening), then sure, it'll be more efficient. On the other hand, lengthening will often require a memory copy because vector::resize preserves all the existing members before the operation.

vector does default-initialization (setting to zero) as well as copies on resize. Do we need either of these behaviors from the container? Would uninitialized memory work? The first thing we're doing is writing into them with query results. Is there some expectation that the buffer be initialized with zero to work correctly?