[Yaml] fixed embedded folded string parsing
merged branch jfsimon/issue-8472 (PR #8841)

This PR was merged into the 2.2 branch.

Discussion
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[Yaml] fixed embedded folded string parsing

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8779

Commits
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566d79c [Yaml] fixed embedded folded string parsing