Fix moderncsqlite errors and rebase onto main (#2832)

This is #2819 but rebased on latest `main`. This PR is against main too
as opposed to the `moderncsqlite` branch.

The main change here is simply:

```go
// add query parameters to the dsn
if strings.Contains(dsn, "?") {
	dsn += "&"
} else {
	dsn += "?"
}

// wait some time before erroring if the db is locked
// https://gitlab.com/cznic/sqlite/-/issues/106#note_1058094993
dsn += "_pragma=busy_timeout%3d10000"
```

### Pull Request Checklist

<!-- Please read
https://matrix-org.github.io/dendrite/development/contributing before
submitting your pull request -->

* [x] I have added tests for PR _or_ I have justified why this PR
doesn't need tests.
* [x] Pull request includes a [sign off below using a legally
identifiable
name](https://matrix-org.github.io/dendrite/development/contributing#sign-off)
_or_ I have already signed off privately

Signed off privately.

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>

cmd/dendrite-demo-pinecone/main.go

@@ -54,8 +54,6 @@ import (
 	pineconeSessions "github.com/matrix-org/pinecone/sessions"
 
 	"github.com/sirupsen/logrus"
-
-	_ "github.com/mattn/go-sqlite3"
 )
 
 var (