Merge remote-tracking branch 'origin/3.1.x' into 4.0.x

# Conflicts:
#	README.adoc
#	docs/pom.xml
#	docs/src/main/asciidoc/README.adoc
#	pom.xml
#	spring-cloud-openfeign-core/pom.xml
#	spring-cloud-openfeign-core/src/test/java/org/springframework/cloud/openfeign/encoding/Invoices.java
#	spring-cloud-openfeign-core/src/test/java/org/springframework/cloud/openfeign/test/EqualsAndHashCodeAssert.java
#	spring-cloud-openfeign-dependencies/pom.xml
#	spring-cloud-starter-openfeign/pom.xml

Author: OlgaMaciaszek

README.adoc

@@ -9,8 +9,6 @@ image::https://github.com/spring-cloud/spring-cloud-openfeign/workflows/Build/ba
 
 image:https://codecov.io/gh/spring-cloud/spring-cloud-openfeign/branch/4.0.x/graph/badge.svg["Codecov", link="https://app.codecov.io/gh/spring-cloud/spring-cloud-openfeign/tree/4.0.x"]
 
-image:https://api.codacy.com/project/badge/Grade/97b04c4e609c4b4f86b415e4437a6484["Codacy code quality", link="https://www.codacy.com/app/Spring-Cloud/spring-cloud-openfeign?utm_source=github.com&utm_medium=referral&utm_content=spring-cloud/spring-cloud-openfeign&utm_campaign=Badge_Grade"]
-
 :doctype: book
 :idprefix:
 :idseparator: -

docs/src/main/asciidoc/README.adoc

@@ -2,8 +2,6 @@ image::https://github.com/spring-cloud/spring-cloud-openfeign/workflows/Build/ba
 
 image:https://codecov.io/gh/spring-cloud/spring-cloud-openfeign/branch/4.0.x/graph/badge.svg["Codecov", link="https://app.codecov.io/gh/spring-cloud/spring-cloud-openfeign/tree/4.0.x"]
 
-image:https://api.codacy.com/project/badge/Grade/97b04c4e609c4b4f86b415e4437a6484["Codacy code quality", link="https://www.codacy.com/app/Spring-Cloud/spring-cloud-openfeign?utm_source=github.com&utm_medium=referral&utm_content=spring-cloud/spring-cloud-openfeign&utm_campaign=Badge_Grade"]
-
 include::_attributes.adoc[]
 
 include::intro.adoc[]