feat(isMobilePhone): update phone regex for Cameroon fr-CM

[2p4b]

update phone regex to match both mobile and fix IDS numbers for Cameroon fr-CM

Checklist

• [x] PR contains only changes related; no stray files, etc.
• [ ] README updated (where applicable)
• [x] Tests written (where applicable)
• [x] References provided in PR (where applicable)

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