statistics: add idx_create_time for stats_meta_history and stats_history (#44195)

[ti-chi-bot]

This is an automated cherry-pick of #44195

What problem does this PR solve?

Issue Number: close #44169

Problem Summary:

What is changed and how it works?

1. Add index idx_create_time(create_time) for both mysql.stats_meta_history and mysql.stats_history. With the index, SELECT and DELETE statements of stats history GC would be more efficient.
2. Reserve some bootstrap version slots(147-166) for patches for v7.1.x. Just the same thing as session: fix upgrade #40182 did.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

Create a table. Do insert and analyze several times.

set @@global.tidb_historical_stats_duration=1s;

Observe GCStats SQLs on dashboard.

• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• qw4990
• winoros

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[hawkingrei]

/merge

[ti-chi-bot]

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

Commit hash: 4e16632