Webcompat reporter should not be shown for internal pages

[srirambv]

Description

Webcompat reporter should not be shown for internal pages

Steps to Reproduce

1. Install nightly
2. Open brave://settings
3. Menu -> Report broken site brings up compat reporter

Actual result:

Expected result:

Option should only work on sites and not on internal pages as shields is disabled on internal pages

Reproduces how often:

Easy

Brave version (brave://version info)

Brave	1.3.44 Chromium: 78.0.3904.108 (Official Build) nightly (64-bit)
Revision	4b26898a39ee037623a72fcfb77279fce0e7d648-refs/branch-heads/3904@{#889}
OS	Linux

Version/Channel Information:

• Can you reproduce this issue with the current release? N/A
• Can you reproduce this issue with the beta channel? N/A
• Can you reproduce this issue with the dev channel? N/A
• Can you reproduce this issue with the nightly channel? Yes

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? N/A
• Does the issue resolve itself when disabling Brave Rewards? N/A
• Is the issue reproducible on the latest version of Chrome? N/A

Miscellaneous Information:

[diracdeltas]

webcompat reporter should probably only be shown for http(s) pages?

[rebron]

cc: @antonok-edm Can you take a look?