Fix failing tests on Strawberry Perl (5.44 in preparation)

[esabol]

This PR is intended to fix the two failing tests in t/02attribs.t discovered by @shawnlaffan in #96 (comment) when preparing Strawberry Perl 5.44 for release. A fix identical to this pull request was confirmed to have fixed the issue on Strawberry Perl in #96 (comment).

Notes on the changes to t/02attribs.t:

The added $dbh->rollback()s ensure a clean transaction state before the next ParamValues checks That way the tests do not depend on the “commands ignored until end of transaction block” behavior that is fragile on Windows.

The (SELECT 1/0) is evaluated at execution time, after binds, so ShowErrorStatement still gets a full ParamValues map. The same pattern works for both $sth->execute and $dbh->do.

Regarding the changes to t/04misc.t:

This is a test expectation issue caused by Windows' case-insensitive filesystems. I'm surprised we haven't seen a report of this on macOS? We could just skip these tests if $^O =~ /Win32|msys|cygwin/i (and macOS/Darwin?), but I have chosen to add the error messages reported on Strawberry Perl to the expected regex.

[shawnlaffan]

Regarding the changes to t/04misc.t:

This is a test expectation issue caused by Windows' case-insensitive filesystems. I'm surprised we haven't seen a report of this on macOS? We could just skip these tests if $^O =~ /Win32|msys|cygwin/i (and macOS/Darwin?), but I have chosen to add the error messages reported on Strawberry Perl to the expected regex.

These tests are perhaps best skipped on Windows as its case insensitivity means DBD::pg causes DBD::Pg to be loaded. The expected failure thus does not happen and a slew of redefined warnings is printed to STDERR.