Closes gh-31097

This commit optimizes ClassUtils#getMostSpecificMethod which is
a method frequently invoked in typical Spring applications.

It refines ClassUtils#isOverridable by considering static and
final modifiers as non overridable and optimizes its implementation.

Closes gh-31100

Beginning with Java 16, inner classes may contain static members. We
therefore need to search for @DynamicPropertySource methods in the
current class after searching enclosing classes so that a local
@DynamicPropertySource method can override properties registered in an
enclosing class.

However, since Spring Framework 5.3.x is built using Java 8, this
commit removes DynamicPropertySourceOverridesEnclosingClassTests since
it declares a static method in a @Nested (inner) test class, which
results in a compiler error on Java 8.

See https://bugs.openjdk.org/browse/JDK-8254321
See gh-31085

Prior to this commit, a dynamic property registered via a
@DynamicPropertySource method in a @Nested test class was not able to
override a property registered via a @DynamicPropertySource method in
the enclosing class.

See gh-26091
Closes gh-31083

Closes gh-31067

Reuses ValidationAnnotationUtils which is slightly optimized for the detection of Spring's Validated annotation now, also to the benefit of common web scenarios.

Closes gh-21852

(cherry picked from commit c7269fee)

(cherry picked from commit 2ce75dc4)

See gh-20189

(cherry picked from commit 8b3ddeed)

Closes gh-31047

(cherry picked from commit 389238f6)

Closes gh-26250

See gh-31034

(cherry picked from commit d781f299)

Closes gh-31034

(cherry picked from commit 6fc4898a)

Leave potential interruption up to scheduler shutdown.

Closes gh-31019

(cherry picked from commit 6fc5a782)

(cherry picked from commit 2aae0a4e)

Closes gh-27781

(cherry picked from commit 6e5af9dc)

Closes gh-30359

(cherry picked from commit 7e6612a9)

(cherry picked from commit abbea398)

(cherry picked from commit bbde68c4)

(cherry picked from commit fdf1418d)

Closes gh-30932

(cherry picked from commit 5bcf5c6f)

(cherry picked from commit 3a9e0ea8)

(cherry picked from commit bbcc788f)

Closes gh-30906

(cherry picked from commit 616f728a)

See gh-30883

(cherry picked from commit 161a7176)

(cherry picked from commit 3a278cc6)

Aligned with shortcut handling in AutowiredAnnotationBeanPostProcessor.
Includes minor MethodInvoker optimization for pre-resolved targetClass.

Closes gh-30883

(cherry picked from commit 6183f068)

Closes gh-25074