fix: resolve small issues in db transactions (#5522)

* fix: use the db transaction reader and writer

* fix: internal/server: use ctx when scanning rows

* fix(host): pass db tx reader/writer into helper funcs

* fix: more precise nil check against db.Reader & db.Writer

---------

Co-authored-by: Johan Brandhorst-Satzkorn <johan.brandhorst@gmail.com>

internal/auth/oidc/repository_auth_method.go

@@ -179,7 +179,7 @@ func (r *Repository) upsertAccount(ctx context.Context, am *AuthMethod, IdTokenC
 			var rowCnt int
 			for rows.Next() {
 				rowCnt += 1
-				err = r.reader.ScanRows(ctx, rows, &result)
+				err = reader.ScanRows(ctx, rows, &result)
 				if err != nil {
 					return errors.Wrap(ctx, err, op, errors.WithMsg("unable to scan rows for account"))
 				}

internal/auth/oidc/repository_managed_group_members.go

@@ -11,6 +11,7 @@ import (
 	"github.com/hashicorp/boundary/internal/errors"
 	"github.com/hashicorp/boundary/internal/kms"
 	"github.com/hashicorp/boundary/internal/oplog"
+	"github.com/hashicorp/boundary/internal/util"
 )
 
 // SetManagedGroupMemberships will set the managed groups for the given account
@@ -207,7 +208,7 @@ func (r *Repository) ListManagedGroupMembershipsByMember(ctx context.Context, wi
 		limit = opts.withLimit
 	}
 	reader := r.reader
-	if opts.withReader != nil {
+	if !util.IsNil(opts.withReader) {
 		reader = opts.withReader
 	}
 	var mgs []*ManagedGroupMemberAccount
@@ -232,7 +233,7 @@ func (r *Repository) ListManagedGroupMembershipsByGroup(ctx context.Context, wit
 		limit = opts.withLimit
 	}
 	reader := r.reader
-	if opts.withReader != nil {
+	if !util.IsNil(opts.withReader) {
 		reader = opts.withReader
 	}
 	var mgs []*ManagedGroupMemberAccount

internal/auth/repository_auth_method.go

@@ -147,7 +147,7 @@ func (amr *AuthMethodRepository) ListDeletedIds(ctx context.Context, since time.
 	var deletedAuthMethodIDs []string
 	var transactionTimestamp time.Time
 	if _, err := amr.writer.DoTx(ctx, db.StdRetryCnt, db.ExpBackoff{}, func(r db.Reader, w db.Writer) error {
-		rows, err := amr.writer.Query(ctx, listDeletedIdsQuery, []any{sql.Named("since", since)})
+		rows, err := w.Query(ctx, listDeletedIdsQuery, []any{sql.Named("since", since)})
 		if err != nil {
 			return errors.Wrap(ctx, err, op)
 		}