Get wrong value for thread body when adding explanation post

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: Master
• Fix Version/s: Master
• Component/s: Message Boards
• Labels:
  • QA-AUTOMATION
• Fix Priority: 3
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/70817
• Bug Type: Regression Bug
• QA Test Name:
  • LocalFile.PGMessageboards#MoveMBCategory1ThreadWithExplanationPostToCategory2
• QA Test Score: 3

Steps to reproduce:

1. Add Message Boards on page
2. Add two categories named ca1 and ca2
3. Add a new thread named Thread1 under ca1
4. Move Thread1 to ca2 and check add explanation post
5. Type 'MB Explanation Post Subject' into subject field and type 'MB Explanation Post Body' into body field
6. Click move

Current behavior:
For the explanation body field shows MB Explanation Post Subject, instead of MB Explanation Post Body

Expected behavior:
For the explanation field shows MB Explanation Post Body