Update dependency org.springdoc:springdoc-openapi-ui to v1.6.4

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.springdoc:springdoc-openapi-ui (source)	1.6.3 -> 1.6.4

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Release Notes

springdoc/springdoc-openapi

v1.6.4

Added

• Add support out of the box for MultipartRequest
• #​1418 - Support for therapi-runtime-javadoc 0.13.0.

Changed

• #​1415 - Moving PageableDefault support to springdoc-openapi-common
• #​1424 - Update classgraph dependency to 4.8.138

Fixed

• #​1407 - Fix issue number in 1.6.3 CHANGELOG
• #​1421 - Actuator endpoints have 2 appended to operationId
• #​1425 - Parameter 2 of method indexPageTransformer in org.springdoc.webmvc.ui.SwaggerConfig required a single bean, but 2 were found

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Configuration

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[coveralls]

Pull Request Test Coverage Report for Build #798

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 97.605%

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Totals
Change from base Build #796:	0.0%
Covered Lines:	652
Relevant Lines:	668

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💛 - Coveralls