Add midterm 22 solutions

.gitlab-ci.yml

build.sbt

...la/benchmarks/midterm22/AbstractCollectionBenchmark.scala

...main/scala/benchmarks/midterm22/CollectionBenchmark.scala

src/main/scala/benchmarks/midterm22/Part2Benchmark.scala

src/main/scala/instrumentation/Monitor.scala

src/main/scala/midterm22/Mock1.scala

src/main/scala/midterm22/Mock2.scala

src/main/scala/midterm22/Part1.scala

src/main/scala/midterm22/Part2.scala

src/main/scala/midterm22/Part3.scala

src/main/scala/midterm22/Part4.scala

src/main/scala/midterm22/Part6.scala

src/main/scala/midterm22/Part7.scala

src/main/scala/midterm22/Part8.scala

src/main/scala/midterm22/appendix/appendix.scala

src/main/scala/midterm22/common.scala

src/test/scala/instrumentation/MockedMonitor.scala

src/test/scala/instrumentation/Scheduler.scala

src/test/scala/instrumentation/Stats.scala