Fix serialization macros with no member variables

[GhostVaibhav]

This PR builds upon the previous PR opened for the same issue and updates the relevant files in the relevant places for the same behaviour intended as in the original PR. This is the link to the original PR - #4323

• The changes are described in detail, both the what and why.
• If applicable, an existing issue is referenced.
• The Code coverage remained at 100%. A test case for every new line of code.
• If applicable, the documentation is updated.
• The source code is amalgamated by running make amalgamate.

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[gregmarr]

See this comment for a less intrusive suggestion: #4994 (comment)