Update amundsendev/amundsen-frontend Docker tag to v4.3.0

This MR contains the following updates:

Package	Type	Update	Change
amundsendev/amundsen-frontend		minor	4.2.0 -> 4.3.0
amundsendev/amundsen-frontend	ironbank-docker	minor	4.2.0 -> 4.3.0
amundsendev/amundsen-frontend	stage	minor	4.2.0 -> 4.3.0

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