chore: added vscode files to .gitignore

[Strum355]

As requested in #3549 (comment)

[monperrus]

Thanks. It seems to me that *.gradle would remove build.gradle. WDYT?

[Strum355]

I did this under the assumption that spoon would be staying with Maven and not using Gradle or both (having to maintain both Maven and Gradle files). If something else is under consideration, I'd be happy to adjust for it

[monperrus]

FYI, we already have some gradle in subprojects, see https://github.com/INRIA/spoon/blob/master/spoon-dataflow/build.gradle

[Strum355]

Is it desirable to not gitignore gradle files at the root of the repo which exists as a maven project? If so, I can amend the gitignore to reflect that.
As it currently exists, these gitignore changes only affect from the root of the repo, so the files in spoon-dataflow/ would be unaffected.

[monperrus]

let's ignore vscode only, to avoid confusion

[monperrus]

Thanks!