InApp Button stroke width is customizable

[laura-turo]

What do these changes do?

This PR adds the functionality to edit the stroke/border width for the InApp buttons.

Apps that want to override the stroke width in InApp Message buttons, can override the default value (2dp) by adding this to their resources (res/{values|dimens|any_name}.xml) file:

<resources>
	<integer name="ua_iam_button_stroke_width_dps">1</integer>
</resources>

Why are these changes necessary?

These changes will add flexibility to InApp Messages to get in line with the app's design.

How did you verify these changes?

Verification Screenshots:

Before	After (default)	After (1dp)

To override the stroke width I added <integer name="ua_iam_button_stroke_width_dps">1</integer> in
~/sample/src/main/res/values/dimens.xml

[jyaganeh]

Hi @laura-turo, thanks for the PR! I'd be happy to get this merged in, but first, could you please fill out our contribution agreement ?

[laura-turo]

Hi @laura-turo, thanks for the PR! I'd be happy to get this merged in, but first, could you please fill out our contribution agreement ?

@jyaganeh Thank you! I just filled it out

[jyaganeh]

@laura-turo I'll get this merged and start prepping a release. Thanks again!