pp-jobs-dialog: Modernize the UI

In pp-jobs-row

• Port to AdwActionRow
• Add tooltips to all buttons and make them flat
• Set the state label as a suffix widget and add the .dim-label style class to it

In pp-jobs-dialog

• Port to AdwDialog (#2952)
• Use AdwPreferencesPage, AdwPreferencesGroup and AdwStatusPage
• Remove the .view style class
• Add .boxed-list style class to the jobs list box
• Add mnemonic to the "Clear All" button

Before	After