BAEL-2200 and BAEL-2287 README updates (#5487)

* BAEL-1766: Update README

* BAEL-1853: add link to article

* BAEL-1801: add link to article

* Added links back to articles

* Add links back to articles

* BAEL-1795: Update README

* BAEL-1901 and BAEL-1555 add links back to article

* BAEL-2026 add link back to article

* BAEL-2029: add link back to article

* BAEL-1898: Add link back to article

* BAEL-2102 and BAEL-2131 Add links back to articles

* BAEL-2132 Add link back to article

* BAEL-1980: add link back to article

* BAEL-2200: Display auto-configuration report in Spring Boot

* BAEL-2253: Add link back to article

* BAEL-2200 BAEL-2287 Add links back to articles

core-java-collections/README.md

@@ -55,3 +55,4 @@
 - [Sort a HashMap in Java](https://www.baeldung.com/java-hashmap-sort)
 - [Finding the Highest Value in a Java Map](https://www.baeldung.com/java-find-map-max)
 - [Operating on and Removing an Item from Stream](https://www.baeldung.com/java-use-remove-item-stream)
+- [An Introduction to Synchronized Java Collections](https://www.baeldung.com/java-synchronized-collections)

spring-boot/README.MD

@@ -34,3 +34,4 @@ The "REST With Spring" Classes: http://bit.ly/restwithspring
 - [Introduction to Chaos Monkey](https://www.baeldung.com/spring-boot-chaos-monkey)
 - [Spring Component Scanning](https://www.baeldung.com/spring-component-scanning)
 - [Load Spring Boot Properties From a JSON File](https://www.baeldung.com/spring-boot-json-properties)
+- [Display Auto-Configuration Report in Spring Boot](https://www.baeldung.com/spring-boot-auto-configuration-report)