BUG/REG: fix float64index -> mixed float assignment
Merge pull request #7368 from cpcloud/fix-float-mixed

BUG/REG: fix float64index -> mixed float assignment
BUG: infer_freq results in None with hourly timezone
BUG: DatetimeIndes.insert doesnt preserve name and tz
Merge pull request #7299 from sinhrks/insert

BUG: DatetimeIndex.insert doesnt preserve name and tz
Merge pull request #7371 from sinhrks/infer_test

BUG: infer_freq results in None for hourly freq with timezone
Revert "BUG: DatetimeIndes.insert doesnt preserve name and tz"

This reverts commit e22c85626317bc74b33854558e05458f82686b51.
CI: move 3.4 build to mainstream / move 3.2 to experimental
BUG: add fix for opening zero observation dta files