chore: Update billing documentation by removing obsolete sections

src/content/docs/account/billing.mdx

@@ -64,11 +64,6 @@ For more information on how organizations and ownership work, see
 
 ## How We Bill
 
-We have different billing models based on the features you enable for each of
-our products.
-
-### Code Push
-
 Shorebird charges based on successful patch installs. A “patch install” is a
 successful update applied on a customer’s device.
 
@@ -82,7 +77,7 @@ You can view your current patch installs in
 [your accounts page](https://console.shorebird.dev/account) on the Shorebird
 Console. These numbers are updated hourly.
 
-#### Overage Billing
+### Overage Billing
 
 For our monthly plans, we offer optional overage billing. This is turned off by
 default.
@@ -107,7 +102,7 @@ the corresponding number of patches available for your billing cycle.
 
 Overage charges appear on the next month's invoice.
 
-##### Example
+#### Example
 
 If you purchase a Pro plan (which includes 50,000 patch installs) and use
 100,000 patches every month:
@@ -116,8 +111,3 @@ If you purchase a Pro plan (which includes 50,000 patch installs) and use
 - At the start of each subsequent month, you'll will be billed for the 50,000
   patch installs for that month, plus the 50,000 overages from the previous
   month, for a total of $40.
-
-### CI
-
-We are currently working on this and will update this page as our pricing
-solidifies.