Loki/Prometheus: Make sections in log/metrics browser resizable (#54704)

* Make loki label browser resizable

* Make prometheus metric browser resizable

* Remove min-width from Label and Metrics browser

* Remove max-width from Prometheus Metrics Browser

public/app/plugins/datasource/loki/components/LokiLabelBrowser.tsx

@@ -152,6 +152,7 @@ const getStyles = (theme: GrafanaTheme2) => ({
   `,
   valueList: css`
     margin-right: ${theme.spacing(1)};
+    resize: horizontal;
   `,
   valueListWrapper: css`
     border-left: 1px solid ${theme.colors.border.medium};

public/app/plugins/datasource/prometheus/components/PrometheusMetricsBrowser.tsx

@@ -158,6 +158,7 @@ const getStyles = stylesFactory((theme: GrafanaTheme) => ({
   `,
   valueList: css`
     margin-right: ${theme.spacing.sm};
+    resize: horizontal;
   `,
   valueListWrapper: css`
     border-left: 1px solid ${theme.colors.border2};