[Storage] Fixed [#12592]: Fix download blob fail when related sub directory not exist.

[blueww]

Description

Fix issue: #12592

The issue is: when download a file "aa/bb.txt" to c:\dir, when c:\dir\aa not exist, download will fail.
This is caused by a recent code re-orgnize in this cmdlet (in PR #12323), so GetFullReceiveFilePath() might will run 2 times, and the 2nd time will fail. We should only run GetFullReceiveFilePath() once for the cmdlet.

Checklist

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