test: add test tags

Author: jvsena42

app/src/main/java/to/bitkit/ui/components/Keyboard.kt

@@ -11,6 +11,7 @@ import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.text.TextStyle
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextAlign
@@ -68,7 +69,7 @@ private fun KeyboardButton(
                 onClick(text)
             },
             onClickLabel = text
-        ),
+        ).testTag("KeyboardButton_$text"),
     )
 }