fix: escape program_name for MySQL (#1717)

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🛠️ Fixes #<issue_number_goes_here>

internal/sources/cloudsqlmysql/cloud_sql_mysql.go

@@ -18,6 +18,7 @@ import (
 	"context"
 	"database/sql"
 	"fmt"
+	"net/url"
 	"slices"
 
 	"cloud.google.com/go/cloudsqlconn/mysql/mysql"
@@ -119,7 +120,7 @@ func initCloudSQLMySQLConnectionPool(ctx context.Context, tracer trace.Tracer, n
 		}
 	}
 	// Tell the driver to use the Cloud SQL Go Connector to create connections
-	dsn := fmt.Sprintf("%s:%s@cloudsql-mysql(%s:%s:%s)/%s?connectionAttributes=program_name:%s", user, pass, project, region, instance, dbname, userAgent)
+	dsn := fmt.Sprintf("%s:%s@cloudsql-mysql(%s:%s:%s)/%s?connectionAttributes=program_name:%s", user, pass, project, region, instance, dbname, url.QueryEscape(userAgent))
 	db, err := sql.Open(
 		"cloudsql-mysql",
 		dsn,