Cleanup Brave Ads frequency capping

[tmancey]

No description provided.

[btlechowski]

Verification passed on

Brave	1.50.93 Chromium: 111.0.5563.64 (Official Build) beta (64-bit)
Revision	c710e93d5b63b7095afe8c2c17df34408078439d-refs/branch-heads/5563@{#995}
OS	Ubuntu 18.04 LTS

Verified test plan from brave/brave-core#17022

NTP SI - 1 hour cap:

[6576:6576:0405/161749.168650:VERBOSE2:permission_rule_util.cc(25)] New tab page ad cannot be shown as minimum wait time has not passed
[6576:6576:0405/161749.169629:VERBOSE1:new_tab_page_ad_serving.cc(65)] New tab page ad not served: Not allowed due to permission rules
[6576:6576:0405/161749.170450:VERBOSE1:ads_service_impl.cc(876)] Failed to prefetch new tab page ad

NTP SI - ads per day

[6924:6924:0405/162100.554493:VERBOSE2:permission_rule_util.cc(25)] You have exceeded the allowed new tab page ads per day
[6924:6924:0405/162100.555040:VERBOSE1:new_tab_page_ad_serving.cc(65)] New tab page ad not served: Not allowed due to permission rules
[6924:6924:0405/162100.555342:VERBOSE1:ads_service_impl.cc(876)] Failed to prefetch new tab page ad

NTP SI - ads per hour

[7466:7466:0405/162452.091051:VERBOSE2:permission_rule_util.cc(25)] You have exceeded the allowed new tab page ads per hour
[7466:7466:0405/162452.091563:VERBOSE1:new_tab_page_ad_serving.cc(65)] New tab page ad not served: Not allowed due to permission rules
[7466:7466:0405/162452.093083:VERBOSE1:ads_service_impl.cc(876)] Failed to prefetch new tab page ad