Fix for multible tags in @Operation annotation

[ugrave]

This PR fixed #11464.

If multble tags are defined the spring generator (with swagger2 annotations) insert a tag attribute for each tag which is defined in the spec.

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[cachescrubber]

@ugrave Thanks for your contribution. Could you update the swagger1 @apioperation as well? Otherwise, the PR looks good.

@welshm, @wing328 FYI.

[welshm]

Might be good to fix the typo - multiple - so that any future reader doesn't need to be unsure of the typo

[ugrave]

@ugrave Thanks for your contribution. Could you update the swagger1 @apioperation as well? Otherwise, the PR looks good.

@welshm, @wing328 FYI.

Changed also the @apioperation.
Note that the tag attribute is know only added if any tag is set.
Before the tag attribute was always there. If no attribute was given an empy value was set (tag = {})

[tofi86]

@wing328 issue #11464 happens for me when switching from 5.3.x to 5.4.0 and when using the new osa3 flag introduced with #9775 in 5.3.1. Any chance to get this fix into 5.4.x instead of 6.0.0 milestone?

[wing328]

Tested with updated samples and the result is good:

[INFO] --- maven-surefire-plugin:2.22.2:test (default-test) @ spring-cloud-date-time ---
[INFO] No tests to run.
[INFO] 
[INFO] --- maven-jar-plugin:3.2.0:jar (default-jar) @ spring-cloud-date-time ---
[INFO] Building jar: /Users/williamcheng/Code/openapi-generator/samples/client/petstore/spring-cloud-date-time/target/spring-cloud-date-time-1.0.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  4.426 s
[INFO] Finished at: 2022-02-10T14:43:23+08:00
[INFO] ------------------------------------------------------------------------

[wing328]

Samples updated via 376bf6c