Fix unconditional overwrite of resolved fallbackFactory in FeignClientsRegistrar

[seonwooj0810]

Fixes gh-1367

Summary

FeignClientsRegistrar.eagerlyRegisterFeignClientBeanDefinition resolves the fallbackFactory attribute via ClassUtils.resolveClassName(...) when it is supplied as a String, but the very next line unconditionally re-sets the same property to the raw attribute value, discarding the resolved Class and rendering the resolution dead code:

https://github.com/spring-cloud/spring-cloud-openfeign/blob/main/spring-cloud-openfeign-core/src/main/java/org/springframework/cloud/openfeign/FeignClientsRegistrar.java#L239-L244

Object fallbackFactory = attributes.get(\"fallbackFactory\");
if (fallbackFactory != null) {
    definition.addPropertyValue(\"fallbackFactory\", fallbackFactory instanceof Class ? fallbackFactory
            : ClassUtils.resolveClassName(fallbackFactory.toString(), null));
}
definition.addPropertyValue(\"fallbackFactory\", attributes.get(\"fallbackFactory\")); // unconditional overwrite

The duplicate, unconditional addPropertyValue mirrors a pattern that the same method already gets right for fallback (lines 234-238 — single conditional set, no overwrite) and that the lazy registration path also gets right (lazilyRegisterFeignClientBeanDefinition, lines 288-292). It looks unintentional.

Change

Remove the duplicate line so the resolved value survives.

Test plan

• ./mvnw -pl spring-cloud-openfeign-core -am test -Dtest=FeignClientsRegistrarTests — 15 tests, 0 failures, 0 errors, 1 skipped (existing testFallback and testFallbackFactory still pass with the Class<?> annotation path).

[ryanjbaxter]

Can you please sign your commit so the DCO passes?

Could you submit the PR against the 4.3.x branch?

[seonwooj0810]

Thanks for the review, @ryanjbaxter!

I've rebased the commit onto 4.3.x and added a Signed-off-by so DCO should pass now. The PR base has also been switched from main to 4.3.x. Please take another look when you have a moment.