build(deps): bump rxjava from 2.1.12 to 2.2.21#3

dependabot[bot] wants to merge 1 commit intodevelopglcj/plc4x:developfrom

dependabot/maven/io.reactivex.rxjava2-rxjava-2.2.21glcj/plc4x:dependabot/maven/io.reactivex.rxjava2-rxjava-2.2.21Copy head branch name to clipboard