upgrade major version to v7 for meets the specification of go module

[wys1203]

Since PR #264 enabled the go module, it‘s better to follow the specification of the go module to upgrade the major version.

Currently, The latest version of package still stuck at v1.3.0 pkg.go.dev This change will help the version control back to the major line

[CLAassistant]

All committers have signed the CLA.

[codecov-io]

Codecov Report

Merging #273 (d9de242) into master (22cd2d5) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #273   +/-   ##
=======================================
  Coverage   77.66%   77.66%           
=======================================
  Files          36       36           
  Lines        2288     2288           
=======================================
  Hits         1777     1777           
  Misses        392      392           
  Partials      119      119           

Impacted Files	Coverage Δ
linebot/httphandler/httphandler.go	71.42% <ø> (ø)

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[kkdai]

Is this related to issue #274 ?

[wys1203]

Is this related to issue #274 ?

Yes, exactly. However, After we enabled the go module at the tag v7.9.0, We can’t go get github.com/line/line-bot-sdk-go v7.9.0+incompatible like we used to.

The expected behavior would be go get: github.com/line/[email protected]: invalid version: module contains a go.mod file, so major version must be compatible: should be v0 or v1, not v7.

This PR will fix the issue by following the module specification.

[kkdai]

LGTM

[kkdai]

Thank you @wys1203. I am going to release new version to fixed #274