Update to use a newer version of codecov github action

[Lan2u]

Relates to issue #378.

It changes the following:

• Updated codecov action version specified to 1.0.7 (latest version) to try and see if this fixes the problem with tokenless codecov not working.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@640b76e). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #436   +/-   ##
=========================================
  Coverage          ?   66.72%           
=========================================
  Files             ?      123           
  Lines             ?     8809           
  Branches          ?        0           
=========================================
  Hits              ?     5878           
  Misses            ?     2931           
  Partials          ?        0           

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[Lan2u]

Seems to be working, https://codecov.io/github/boa-dev/boa/commit/eb493f14a8095bcc38d9c5ce8b107db30c4d2783.

[jasonwilliams]

1.0.6 fixed this:
Add tokenless upload functionality by passing the GITHUB_RUN_ID environment variable to properly tag the build. This allows Codecov to locate the build via GitHub's API and validate the coverage upload