session: cleanup check_dev_2 scaffolding

[tisonkun]

As PingCAP-QE/ci#975 merged, check_dev_2 doesn't specially handle session/ any more. session/ is a now normal package.

Issue Number: ref #26864

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• Defined2014
• hawkingrei

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[tisonkun]

/cc @hawkingrei @xhebox

[sre-bot]

Code Coverage Details: https://codecov.io/github/pingcap/tidb/commit/db9b6477520d19dc7cd22b8424ef113a676e5a67

[Defined2014]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 403eefe

[tisonkun]

/run-build

[sre-bot]

TiDB MergeCI notify

🔴 Bad News! [1] CI still failing after this pr merged.
These failed integration tests don't seem to be introduced by the current PR.

CI Name	Result	Duration	Compare with Parent commit
idc-jenkins-ci-tidb/integration-common-test	🔴 failed 3, success 8, total 11	9 min 49 sec	Existing failure
idc-jenkins-ci/integration-cdc-test	🟢 all 34 tests passed	23 min	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-2	🟢 all 28 tests passed	8 min 10 sec	Existing passed
idc-jenkins-ci-tidb/integration-ddl-test	🟢 all 6 tests passed	7 min 54 sec	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-1	🟢 all 26 tests passed	7 min 41 sec	Existing passed
idc-jenkins-ci-tidb/tics-test	🟢 all 1 tests passed	6 min 3 sec	Existing passed
idc-jenkins-ci-tidb/mybatis-test	🟢 all 1 tests passed	5 min 28 sec	Existing passed
idc-jenkins-ci-tidb/common-test	🟢 all 12 tests passed	5 min 9 sec	Existing passed
idc-jenkins-ci-tidb/integration-compatibility-test	🟢 all 1 tests passed	2 min 53 sec	Existing passed
idc-jenkins-ci-tidb/plugin-test	🟢 build success, plugin test success	4min	Existing passed