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>

.github/workflows/dendrite.yml

@@ -269,11 +269,18 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - label: SQLite
+          - label: SQLite native
 
-          - label: SQLite, full HTTP APIs
+          - label: SQLite Cgo
+            cgo: 1
+
+          - label: SQLite native, full HTTP APIs
             api: full-http
 
+          - label: SQLite Cgo, full HTTP APIs
+            api: full-http
+            cgo: 1
+
           - label: PostgreSQL
             postgres: postgres
 
@@ -288,6 +295,7 @@ jobs:
         POSTGRES: ${{ matrix.postgres && 1}}
         API: ${{ matrix.api && 1 }}
         SYTEST_BRANCH: ${{ github.head_ref }}
+        CGO_ENABLED: ${{ matrix.cgo && 1 }}
     steps:
       - uses: actions/checkout@v2
       - name: Run Sytest
@@ -323,11 +331,18 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - label: SQLite
+          - label: SQLite native
 
-          - label: SQLite, full HTTP APIs
+          - label: SQLite Cgo
+            cgo: 1
+
+          - label: SQLite native, full HTTP APIs
             api: full-http
 
+          - label: SQLite Cgo, full HTTP APIs
+            api: full-http
+            cgo: 1
+
           - label: PostgreSQL
             postgres: Postgres
 
@@ -393,6 +408,7 @@ jobs:
         env:
           COMPLEMENT_BASE_IMAGE: complement-dendrite:latest
           API: ${{ matrix.api && 1 }}
+          CGO_ENABLED: ${{ matrix.cgo && 1 }}
         working-directory: complement
 
   integration-tests-done: