remove deprecated ioutil usage

[shota3506]

remove deprecated ioutil usage

[codecov[bot]]

Codecov Report

Merging #147 (821c7f7) into main (7e54b30) will decrease coverage by 0.7%. The diff coverage is 0.0%.

@@           Coverage Diff           @@
##            main    #147     +/-   ##
=======================================
- Coverage   83.2%   82.5%   -0.8%     
=======================================
  Files         14      14             
  Lines       3122    3122             
=======================================
- Hits        2600    2577     -23     
- Misses       522     545     +23     

Flag	Coverage Δ
linux-1.17-nightly	?
linux-1.17-stable	82.5% <0.0%> (ø)
linux-1.18-nightly	?
linux-1.18-stable	82.5% <0.0%> (ø)
linux-1.19-nightly	?
linux-1.19-stable	82.5% <0.0%> (ø)
macos-1.17-nightly	?
macos-1.17-stable	82.5% <0.0%> (ø)
macos-1.18-nightly	?
macos-1.18-stable	82.5% <0.0%> (ø)
macos-1.19-nightly	?
macos-1.19-stable	82.5% <0.0%> (ø)
windows-1.17-nightly	?
windows-1.17-stable	81.7% <0.0%> (ø)
windows-1.18-nightly	?
windows-1.18-stable	81.7% <0.0%> (ø)
windows-1.19-nightly	?
windows-1.19-stable	81.7% <0.0%> (ø)

Impacted Files	Coverage Δ
nvim/plugin/main.go	30.0% <0.0%> (ø)
nvim/api.go	94.1% <0.0%> (-3.1%)	:arrow_down:

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[zchee]

@shota3506 The failed test was caused by the Neovim version. I'll fix it.

[zchee]

@shota3506 All Required tests are passed. I'll merge it.