Issuable sidebar > Update edit buttons

In issuable sidebars, we use a number of Edit buttons to trigger a dropdown for editing the value. These edit buttons do not currently utilize any of our defined Pajamas buttons. In order to migrate to a defined button state, we would need to change the design of the sidebar slightly.

Proposal

Utilize our small tertiary default button for the edit buttons in the sidebar. In order to align the button correctly, this also involves making the dividers full width.

See Figma prototype: https://www.figma.com/proto/M73BcOBI0V6PEZfxvI5sMM/Sketchy-Sketch?node-id=699%3A103&viewport=469%2C515%2C1&scaling=min-zoom&hotspot-hints=0

Shout out to @jeldergl for working through this with me and coming up with the final proposal design/prototype