Update "Pending Contributions" line item in Rewards summary

[Miyayes]

Description

As suggested by design team (@jenn-rhim and @minkyeongshin):

• Update pending contributions line to be this: Pending contributions 12.00 BAT 10.00 USD. It will follow same format as other line items. The "Pending contributions" text itself will be clickable and open up the pending contributions list view.
• Reorder the pending contributions line item to the bottom of the summary, under Monthly Tips.

Existing screenshot of UI for reference:

[MadhaviSeelam]

Verified Passed using

Brave	1.38.75 Chromium: 100.0.4896.60 (Official Build) beta (64-bit)
Revision	6a5d10861ce8de5fce22564658033b43cb7de047-refs/branch-heads/4896@{#875}
OS	Windows 11 Version 21H2 (Build 22000.593)

• Install 1.38.75
• Launch Brave
• Tip unverified user (cnn.com)
• Open brave://rewards and view Rewards Summary
• Verified Pending contributions line is moved to last row below Monthly Tips
• Verified the update to Pending contributions format and it is the same format as others in the summary page - Pending contributions 17.50 BAT 15.28 USD
• Verified Pending contributions is a clickable link and it opens up the Pending contributions list view as this is existing functionality
• Removed all Pending contributions and close the view
• Pending contributions line is no longer displayed

ex1	ex2	ex3

[LaurenWags]

Verified on Google Pixel 3 XL with Android 12 running 1.38.83

• Confirmed "Pending Contributions" line item is the same as desktop / matches description
• Confirmed when "Pending Contributions" is tapped on, it opens the list view

Example	Example

Other testing for "Pending Contributions" on Android can be found under #17038 (comment).

[stephendonner]

Verified PASSED using

Brave	1.38.83 Chromium: 100.0.4896.79 (Official Build) beta (x86_64)
Revision	8fb749dcab8700c24213791969e59deb72fee36f-refs/branch-heads/4896@{#1015}
OS	macOS Version 11.6.5 (Build 20G527)

Steps:

1. installed 1.38.83
2. launched Brave
3. tipped unverified user (cnn.com)
4. opened brave://rewards and viewed Rewards Summary
5. verified Pending contributions line is moved to last row below Monthly Tips
6. verified the update to Pending contributions format and it is the same format as others in the summary page - Pending contributions 5.00 BAT 4.00 USD
7. verified Pending contributions is a clickable link and it opens up the Pending contributions list view as this is existing functionality
8. removed all Pending contributions and closed the view
9. Pending contributions line is no longer displayed

example	example	example	example