fix(operator): convert booleans to Python-compatible values in BubbleChart/ContourPlot/TernaryPlot

common/workflow-operator/src/main/scala/org/apache/texera/amber/operator/visualization/bubbleChart/BubbleChartOpDesc.scala

@@ -105,7 +105,7 @@ class BubbleChartOpDesc extends PythonOperatorDescriptor {
   def createPlotlyFigure(): PythonTemplateBuilder = {
     assert(xValue.nonEmpty && yValue.nonEmpty && zValue.nonEmpty)
     pyb"""
-         |        if $enableColor == 'true':
+         |        if '$enableColor' == 'true':
          |            fig = go.Figure(px.scatter(table, x=$xValue, y=$yValue, size=$zValue, size_max=100, color=$colorCategory))
          |        else:
          |            fig = go.Figure(px.scatter(table, x=$xValue, y=$yValue, size=$zValue, size_max=100))

common/workflow-operator/src/main/scala/org/apache/texera/amber/operator/visualization/contourPlot/ContourPlotOpDesc.scala

@@ -100,7 +100,7 @@ class ContourPlotOpDesc extends PythonOperatorDescriptor {
        |        y = table[$y].values
        |        z = table[$z].values
        |        grid_size = int($gridSize)
-       |        connGaps = True if $connectGaps == 'true' else False
+       |        connGaps = True if '$connectGaps' == 'true' else False
        |
        |        grid_x, grid_y = np.meshgrid(np.linspace(min(x), max(x), grid_size), np.linspace(min(y), max(y), grid_size))
        |        grid_z = griddata((x, y), z, (grid_x, grid_y), method='cubic')

common/workflow-operator/src/main/scala/org/apache/texera/amber/operator/visualization/ternaryPlot/TernaryPlotOpDesc.scala

@@ -101,7 +101,7 @@ class TernaryPlotOpDesc extends PythonOperatorDescriptor {
   /** Returns a Python string that creates the ternary plot figure */
   def createPlotlyFigure(): PythonTemplateBuilder = {
     pyb"""
-       |        if $colorEnabled == 'true' and $colorDataField != "":
+       |        if '$colorEnabled' == 'true' and $colorDataField != "":
        |            fig = px.scatter_ternary(table, a=$firstVariable, b=$secondVariable, c=$thirdVariable, color=$colorDataField)
        |        else:
        |            fig = px.scatter_ternary(table, a=$firstVariable, b=$secondVariable, c=$thirdVariable)