[Windows] Replace Header with PlaceholderText for Title property of Picker#33007

mhrastegari wants to merge 14 commits into

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mhrastegari:32723-replace-header-with-placeholder-on-windows-picker-title-propertymhrastegari/maui:32723-replace-header-with-placeholder-on-windows-picker-title-propertyCopy head branch name to clipboard