filter/firewall-rules fix for double API calls

[tamas-jozsa]

Description

Recent pagination updates to these APIs are causing endpoints to be called twice. This PR aims to fix them.

Has your change been tested?

Unit tests are passing, and I tried this version in cf-terraforming, where it's working as expected

Types of changes

What sort of change does your code introduce/modify?

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• This change is using publicly documented (api.cloudflare.com or developers.cloudflare.com) and stable APIs.

[github-actions]

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[codecov-commenter]

Codecov Report

Merging #1012 (d4e8a80) into master (6c5ea4a) will decrease coverage by 0.08%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #1012      +/-   ##
==========================================
- Coverage   49.06%   48.97%   -0.09%     
==========================================
  Files         108      108              
  Lines       10428    10432       +4     
==========================================
- Hits         5116     5109       -7     
- Misses       4200     4215      +15     
+ Partials     1112     1108       -4     

Impacted Files	Coverage Δ
access_application.go	76.52% <ø> (ø)
access_bookmark.go	72.44% <ø> (ø)
filter.go	39.00% <0.00%> (-3.44%)	⬇️
firewall_rules.go	49.15% <0.00%> (-3.44%)	⬇️

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