docs: update generated_resources.rst

[ingve]

Issue #, if available: N/A

Description of changes:
Added a missing word to the docs/internals/generated_resources.rst file to improve readability.

Description of how you validated changes:
N/A

Checklist:

• Update documentation

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov-io]

Codecov Report

Merging #919 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #919   +/-   ##
========================================
  Coverage    94.66%   94.66%           
========================================
  Files           69       69           
  Lines         3016     3016           
  Branches       561      561           
========================================
  Hits          2855     2855           
  Misses          85       85           
  Partials        76       76

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