fix: prefix search

[andrewbenington]

• Identified the issue which this PR solves.
• Read the CONTRIBUTING document.
• Code builds clean without any errors or warnings.
• Added appropriate tests for any new functionality.
• All new and existing tests passed.
• Added comments in the code, where necessary.
• Ran make check to catch common errors. Fixed any that came up.

Description:

• Searching list pages (users, escalation policies, rotations, schedules, notifications, and services) only shows results that match the order of the search terms.
• Words can be skipped (e.g. the search "Serv Two" will return both "Service Two" and "Service One Two")

Before:

After:

Which issue(s) this PR fixes:
Fixes #3217

Describe any introduced API changes:
Anything using prefixSearch now uses orderedPrefixSearch, which queries with a single regex.

Examples (\m matches beginning of word):
\m{term 1}
\m{term 1}.*\m{term 2}
\m{term 1}.*\m{term 2}.*\m{term 3}

[tony-tvu]

lgtm