fix undefined and null textposition inputs for scatter plot
fix undefined and null textposition inputs for scatter plot

etpinard/plotly.js,aburato/plotly.js,etpinard/plotly.js,asolagmbh/plotly.js,asolagmbh/plotly.js,plotly/plotly.js,plotly/plotly.js,etpinard/plotly.js,aburato/plotly.js,asolagmbh/plotly.js,plotly/plotly.js,plotly/plotly.js