fix QueryRowsPartial getTaggedFieldValueMap func

[fulldog]

When using orm, a problem was found. When you use QueryRowsPartial to get a small number of query fields, the scanner scans the struct in the order it was passed in, causing an err
The following structure:


err：

[fulldog]

@kevin0527 大佬看一下问题

[Issues-translate-bot]

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@kevin0527 big guy look at the problem

[kevwan]

Please check and fix UT.

[fulldog]

@kevwan The bug has been fixed and tested

[kevwan]

Thanks for your PR! Please add unit tests.

[fulldog]

@kevwan sorry for this.
test case is in core/stores/sqlx/orm_test.go,func TestAnonymousStructPr().
that case has been tested in orm_test.go

[codecov]

Codecov Report

Merging #2884 (da986d7) into master (f77e2c9) will decrease coverage by 0.27%.
The diff coverage is 100.00%.

❗ Current head da986d7 differs from pull request most recent head c45ea0c. Consider uploading reports for the commit c45ea0c to get more accurate results

Impacted Files	Coverage Δ
core/stores/sqlx/orm.go	72.52% <100.00%> (+6.43%)	⬆️

... and 29 files with indirect coverage changes