[jdk7u] RFR: 8285357: Update .jcheck/conf file for 7u move to git

[Andrew Brygin]

We have to update the .jcheck/conf for jdk7u in the same manner as it was done for jdk8u-dev: https://github.com/openjdk/jdk8u-dev/commit/4a19c1a65107202800bf8df51684f7255d6ef027

The current version for 7u is openjdk7u341.

-------------

Commit messages:
 - 8285357: Update .jcheck/conf file for 7u move to git

Changes: https://git.openjdk.java.net/jdk7u/pull/1/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk7u&pr=1&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8285357
  Stats: 31 lines in 1 file changed: 29 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk7u/pull/1.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk7u pull/1/head:pull/1

PR: https://git.openjdk.java.net/jdk7u/pull/1