Adding Bitcoin.com widget to NTP [1.15]

[ryanml]

Uplift of: #6681, #6756, #6754
Issue: brave/brave-browser#11982

Approved, please ensure that before merging:

• You have checked CI and the builds, lint, and tests all pass or are not related to your PR.
• You have tested your change on Nightly.
• The PR milestones match the branch they are landing to.

After you merge:

• The associated issue milestone is set to the smallest version that the changes is landed on.

[kjozwiak]

Restarting Win x64 via https://ci.brave.com/job/pr-brave-browser-bitcoin-dot-com-1.15-windows/4/ as dist failed as per https://ci.brave.com/job/pr-brave-browser-bitcoin-dot-com-1.15-windows/3/execution/node/246/log.

04:00:27  SignTool Error: The specified timestamp server either could not be reached or
04:00:27  returned an invalid response.
04:00:27  SignTool Error: An error occurred while attempting to sign: scons-out\opt-win\obj\goopdate\BraveUpdateBroker.exe

Restarting Linux via https://ci.brave.com/job/pr-brave-browser-bitcoin-dot-com-1.15-linux/4/ due to init failing as per https://ci.brave.com/job/pr-brave-browser-bitcoin-dot-com-1.15-linux/3/execution/node/119/log/.

02:15:46  Aborting
02:15:46  error: could not detach HEAD
02:15:46  ----------------------------------------
02:15:46  Error: 49> Unrecognized error, please merge or rebase manually.
02:15:46  49> cd /home/ubuntu/workspace/pr-brave-browser-bitcoin-dot-com-1.15-linux/src/third_party/grpc/src && git rebase --onto 74b981a6a3d9ba17f3acae1d72b9109325ef656d refs/remotes/origin/master

[kjozwiak]

Restarting Linux https://ci.brave.com/job/pr-brave-browser-bitcoin-dot-com-1.15-linux/5/ via using WIPE_WORKSPACE due to init failing as per https://ci.brave.com/job/pr-brave-browser-bitcoin-dot-com-1.15-linux/4/execution/node/119/log/.

14:45:02  Aborting
14:45:02  error: could not detach HEAD
14:45:02  ----------------------------------------
14:45:02  Error: 49> Unrecognized error, please merge or rebase manually.
14:45:02  49> cd /home/ubuntu/workspace/pr-brave-browser-bitcoin-dot-com-1.15-linux/src/third_party/grpc/src && git rebase --onto 74b981a6a3d9ba17f3acae1d72b9109325ef656d refs/remotes/origin/master

[kjozwiak]

Uplift into 1.15.x approved after deliberating with @brave/uplift-approvers. QA has also verified the PR on Nightly as per #6681 (comment), #6756 (comment) & #6754 (comment).