Fix part of #9749: Migrate Preview thumbnail.

[ashutoshc8101]

Overview

1. This fixes part of Migrate directives/controllers to Angular components #9749.
2. This PR does the following: Migrate Preview thumbnail.

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Proof that changes are correct

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[oppiabot]

Hi, @ashutoshc8101, this pull request does not have a "CHANGELOG: ..." label as mentioned in the PR pointers. Assigning @ashutoshc8101 to add the required label. PRs without this label will not be merged. If you are unsure of which label to add, please ask the reviewers for guidance. Thanks!

[oppiabot]

Hi @ashutoshc8101, the build of this PR is stale and this could result in tests failing in develop. Please update this pull request with the latest changes from develop. Thanks!

[kevintab95]

LGTM for codeowner files. Thanks @ashutoshc8101!

[oppiabot]

Unassigning @srijanreddy98 since they have already approved the PR.