Allow for VPN on Beta

[bsclifton]

Test plan

1. Wait until 1.39 is on Beta
2. Try to run steps from Implement Brave VPN on Desktop #15804

Description

Changes needed so that VPN can move from Nightly to Beta with 1.39 😄

1. VPN functionality is tied to the Nightly channel at the moment (via build flag). We should expose this feature on brave://flags/#brave-vpn for Beta also.

2. VPN for Desktop is also requiring that SKU SDK (brave://flags/#skus-sdk) is enabled. We should enable the SKU SDK feature by default

[stephendonner]

Verified PASSED using

Brave	1.39.84 Chromium: 101.0.4951.41 (Official Build) beta (x86_64)
Revision	93c720db8323b3ec10d056025ab95c23a31997c9-refs/branch-heads/4951@{#904}
OS	macOS Version 11.6.5 (Build 20G527)

Followed the testplan at #21598 (comment).

Confirmed, from the testplan:

1. VPN functionality is tied to the Nightly channel at the moment (via build flag). We should expose this feature on brave://flags/#brave-vpn for Beta also.

All three flags are available:

1. brave://flags/#brave-vpn
2. brave://flags/#skus-environment
3. brave://flags/#skus-sdk

SKUs	VPN

2. VPN for Desktop is also requiring that SKU SDK (brave://flags/#skus-sdk) is enabled. We should enable the SKU SDK feature by default

Confirmed via entering window.chrome.brave into the Developer Tools Console yielded window.chrome.braveSkus, without enabling brave://flags/#skus-sdk (left as Default as seen in screenshot).

Steps:

1. install 1.39.84
2. launch Brave using --vmodule="*/skus/*"=1 --enable-logging=stderr
3. set Enable Experimental Brave VPN to Enabled
4. set Experimental SKU Environment to Development
5. click Relaunch
6. load account.brave.software
7. enter basic auth creds for site
8. enter an email address and click Get login link
9. check your email inbox
10. click Log in to Brave or the link in the email
11. click on Browse plans
12. scroll down and click on Buy now for Brave VPN Subscription
13. enter payment details on https://checkout.stripe.com/pay/cs_test…
14. click Subscribe
15. you should get a Complete your purchase... screen
16. click on Complete payment

Confirmed I could successfully (and automatically) connect to VPN via the icon and its toggle, in the URL bar.

example	example	example	example	example
			.

[GeetaSarvadnya]

Verification PASSED on

Brave | 1.39.101 Chromium: 101.0.4951.64 (Official Build) beta (64-bit)
-- | --
Revision | d1daa9897e1bc1d507d6be8f2346e377e5505905-refs/branch-heads/4951@{#1208}
OS | Windows 10 Version 21H2 (Build 19044.1706)

Followed the testplan at #21598 (comment).

Steps:

1. install 1.39.84
2. launch Brave using --vmodule="*/skus/*"=1 --enable-logging=stderr
3. set Enable Experimental Brave VPN to Enabled
4. set Experimental SKU Environment to Development
5. click Relaunch
6. load account.brave.software
7. enter basic auth creds for site
8. enter an email address and click Get login link
9. check your email inbox
10. click Log in to Brave or the link in the email
11. click on Browse plans
12. scroll down and click on Buy now for Brave VPN Subscription
13. enter payment details on https://checkout.stripe.com/pay/cs_test…
14. click Subscribe
15. you should get a Complete your purchase... screen
16. click on Complete payment

Confirmed I could successfully (and automatically) connect to VPN via the icon and its toggle, in the URL bar.

example	example	example	example	example