Fix stacking of Settings menu in the reader on multiple taps (#8002)

* fix : conditional check added to avoid stacking of dialog

In onClickListener, bottom sheet is being opened depending on status of dialog sheet, if it's showing or not.

* chore : refactored conditional logic

* Update ReaderActivity.kt

(cherry picked from commit 30ac94181b)

app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderActivity.kt

@@ -632,9 +632,11 @@ class ReaderActivity : BaseRxActivity<ReaderPresenter>() {
         // Settings sheet
         with(binding.actionSettings) {
             setTooltip(R.string.action_settings)
-
+            val readerSettingSheetDialog = ReaderSettingsSheet(this@ReaderActivity)
             setOnClickListener {
-                ReaderSettingsSheet(this@ReaderActivity).show()
+                if (!readerSettingSheetDialog.isShowing()) {
+                    readerSettingSheetDialog.show()
+                }
             }
 
             setOnLongClickListener {