Added mention of online form

[lwalsh617]

Page to edit

url: https://github.com/department-of-veterans-affairs/vagov-content/blob/wip-decision-reviews-hlr/pages/decision-reviews/higher-level-review.md
Branch: wip-decision-reviews-HLR

Origin of request (internal/stakeholder/user feedback)

Jennifer Lee

Description of what's needed (edits/link changes/additions)

Adding online tool

[va-bot]

⚠️ This content failed to build with the following output:

Error: request to https://prod.cms.va.gov/flags_list failed, reason: connect ECONNREFUSED 127.0.0.1:2001
    at ClientRequest.<anonymous> (/application/node_modules/node-fetch/lib/index.js:1369:11)
    at ClientRequest.emit (events.js:198:13)
    at onerror (/application/node_modules/socks-proxy-agent/node_modules/agent-base/index.js:101:9)
    at callbackError (/application/node_modules/socks-proxy-agent/node_modules/agent-base/index.js:123:5)
    at process._tickCallback (internal/process/next_tick.js:68:7)