Applied fixes and suppressions (sadly) to match psalm/phpstan code quality guidelines

We have a lot of deprecated API in here which shouldn't exist in first place, but that
will luckily disappear with v5.0.0 :-)

composer.json

@@ -67,6 +67,7 @@
     },
     "autoload-dev": {
         "psr-4": {
+            "Ramsey\\Uuid\\Benchmark\\": "tests/benchmark/",
             "Ramsey\\Uuid\\StaticAnalysis\\": "tests/static-analysis/",
             "Ramsey\\Uuid\\Test\\": "tests/"
         }