Fix missing symbols for singlefilehost

[elinor-fung]

The symbol packages were missing symbols for singlefilehost because they weren't being copied to the expected location, resulting in singlefilehost.dbg/pdb not being published. This updates the PrepareSingleFileHostWithEmbeddedDacCore target to copy the symbol file from and to the expected locations (PDB sudbirectory for Windows, next to the binary for non-Windows).

Fixes#71735

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Issue Details

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The symbol packages were missing symbols for singlefilehost because they weren't being copied to the expected location, resulting in singlefilehost.dbg/pdb not being published. This updates the PrepareSingleFileHostWithEmbeddedDacCore target to copy the symbol file from and to the expected locations (PDB sudbirectory for Windows, next to the binary for non-Windows).

Fixes #71735

Author:	elinor-fung
Assignees:	-
Labels:	area-Single-File
Milestone:	-

[agocke]

LGTM, thanks!

[VSadov]

LGTM. Thanks!!