added a deprecated marker in common.thrift

[xtcyclist]

What type of PR is this?

• bug
• feature
• enhancement

What problem(s) does this PR solve?

Issue(s) number:

Close #4986
Related to #4907

Description:

Remove a member in an enum may result in generating inconsistent thrift codes and building errors. Not sure what the exact reason is. But keeping the enmu unchanged avoids this risk.

How do you solve it?

• Add the removed member back (i.e., UNKNOWN_PROP) with a deprecated comment marker.
• It serves as a placeholder to avoid size differences of enum NullType.
• It will never be sent to clients, as UNKNOWN_PROP has been removed in Value.h.

Special notes for your reviewer, ex. impact of this fix, design document, etc:

Checklist:

Tests:

• Unit test(positive and negative cases)
• Function test
• Performance test
• N/A

Affects:

• Documentation affected (Please add the label if documentation needs to be modified.)
• Incompatibility (If it breaks the compatibility, please describe it and add the label.）
• If it's needed to cherry-pick (If cherry-pick to some branches is required, please label the destination version(s).)
• Performance impacted: Consumes more CPU/Memory

Release notes:

Please confirm whether to be reflected in release notes and how to describe:

ex. Fixed the bug .....