Add input secret select to built-in function for interactive input

[k1LoW]

ref: #296

$ cat prompt.yml
desc: Prompt
steps:
  -
    bind:
      twitterID: input("Enter your twitter ID", "default")
  -
    dump: twitterID
$ go run ./cmd/runn/main.go run prompt.yml
Enter your twitter ID [default]: k1LoW
k1LoW
Prompt ... ok

1 scenario, 0 skipped, 0 failures

[github-actions]

Code Metrics Report

	main (d810960)	#297 (ab3336c)	+/-
Coverage	77.0%	76.8%	-0.1%
Code to Test Ratio	1:0.7	1:0.7	-0.0

Details

  |                    | main (d810960) | #297 (ab3336c) |  +/-  |
  |--------------------|----------------|----------------|-------|
- | Coverage           |          77.0% |          76.8% | -0.1% |
  |   Files            |             34 |             34 |     0 |
  |   Lines            |           3380 |           3386 |    +6 |
  |   Covered          |           2601 |           2601 |     0 |
- | Code to Test Ratio |          1:0.7 |          1:0.7 |  -0.0 |
  |   Code             |           7462 |           7476 |   +14 |
  |   Test             |           5199 |           5199 |     0 |

Code coverage of files in pull request scope (75.2% → 73.9%)

Files	Coverage	+/-
option.go	73.9%	-1.3%

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Reported by octocov