Puzzles resolution

java-puzzles/.gitlab-ci.yml

...puzzles/src/test/java/fr/ippon/PlayingWithBigDecimal.java

java-puzzles/src/test/java/fr/ippon/PlayingWithFinally.java

...les/src/test/java/fr/ippon/PlayingWithInstanciations.java

java-puzzles/src/test/java/fr/ippon/PlayingWithInteger.java

java-puzzles/src/test/java/fr/ippon/PlayingWithString.java

java-puzzles/src/test/java/fr/ippon/PlayingWithThreads.java