[Enhancement] Enable tablet internal parallel by default

[ZiheLiu]

What type of PR is this：

• [ ] bug
• [ ] feature
• [x] enhancement
• [ ] refactor
• [ ] others

Problem Summary(Required) ：

Enable tablet internal parallel in session variables by default.

Checklist:

• [ ] I have added test cases for my bug fix or my new feature
• [ ] I have added user document for my new feature or new function

[ZiheLiu]

@Mergifyio backport branch-2.4

[mergify[bot]]

backport branch-2.4

✅ Backports have been created

• #9990 [Enhancement] Enable tablet internal parallel by default (backport #9927) has been created for branch branch-2.4

[ZiheLiu]

run starrocks_admit_test

[ZiheLiu]

run starrocks_fe_unittest

[ZiheLiu]

run starrocks_admit_test

[ZiheLiu]

run starrocks_fe_unittest

[ZiheLiu]

run starrocks_admit_test

[ZiheLiu]

run starrocks_admit_test

[sonarcloud[bot]]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[wanpengfei-git]

[FE PR Coverage Check]

:heart_eyes: pass : 1 / 1 (100.00%)

file detail

	path	covered_line	new_line	coverage	not_covered_line_detail
:large_blue_circle:	com/starrocks/qe/SessionVariable.java	1	1	100.00%	[]

[wanpengfei-git]

run starrocks_admit_test