[jdk11u-dev] RFR: 8244966: Add .vscode to .hgignore and .gitignore

[SendaoYan]

Hi all,
This is backport of [JDK-8244966](https://bugs.openjdk.org/browse/JDK-8244966), to add `.vscode` to `.gitignore`.
It's not clean because in jdk11u-dev the `.hgignore` has been deleted by JDK-8254178.
Trivial fix, no risk.

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Commit messages:
 - Backport d3e0c4ce9c22e69e6eac17257a02d5e796b84bac

Changes: https://git.openjdk.org/jdk11u-dev/pull/2883/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2883&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8244966
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2883.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2883/head:pull/2883

PR: https://git.openjdk.org/jdk11u-dev/pull/2883