Fix number check for option value

[xuchaoying]

• Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

bug fix

• What is the related issue? (Use #issue_id to relate an open issue)

• Does this PR introduce a breaking change?

no

• Other information:

[codecov]

Codecov Report

Merging #77 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master     #77   +/-   ##
======================================
  Coverage    91.8%   91.8%           
======================================
  Files          44      44           
  Lines        1561    1561           
======================================
  Hits         1433    1433           
  Misses        128     128

Impacted Files	Coverage Δ
packages/svrx/lib/configure/index.js	98.69% <100%> (ø)	⬆️

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