[Security Solution][Explore][EUI visual refresh] rename color variables

[angorayc]

Context

Changes are made to EUI that will be visible to end-users in Kibana:

• Updated all colors in EUI
• Reduce the topmost font weights and sizes (think titles and headings) These changes are available in a new theme called Borealis.

See parent ticket for how to use the new theme and labels to add to the PR for tracking

Description

All references to renamed tokens have been updated to use the new token name.

[!IMPORTANT] The naming of these tokens has changed as well. Please update all references to use the new token name. The old token names are now deprecated.

# previous color token -> new color token
primaryText -> textPrimary
accentText -> textAccent
between this and textSuccess.
warningText -> textWarning
dangerText -> textDanger
text -> textParagraph
title -> textHeading
subduedText -> textSubdued
disabledText -> textDisabled

[elasticmachine]

Pinging @elastic/security-solution (Team: SecuritySolution)

[elasticmachine]

Pinging @elastic/security-threat-hunting (Team:Threat Hunting)

[elasticmachine]

Pinging @elastic/security-threat-hunting-explore (Team:Threat Hunting:Explore)