Cherry pick installer window size changes to release/6.2#430

mhegazy wants to merge 2 commits intoswiftlang:release/6.2swiftlang/swift-installer-scripts:release/6.2from

mhegazy:cherry-pick-fix-install-progress-positionmhegazy/swift-installer-scripts:cherry-pick-fix-install-progress-positionCopy head branch name to clipboard