Offer more line end-point symbols in Chart Widget

[AmyRoust]

When setting up a line chart with the Chart Widget in Experience Builder, you have minimal options for the "Value Point" styling. You can have no endpoints (flat end to the line) or you can have circles of varying size and color.

It would be nice to have more than one symbol for the value points (squares and triangles at minimum, with the option to rotate them to get diamonds or arrows pointing in specific directions respectively). That gives the designer more options for making their data points distinct for people who are living with vision impairments such as color blindness.