Update Dockerfile.tmpl (#1147)

Unpin torchmetrics version

Author: tsuga

Dockerfile.tmpl

@@ -506,8 +506,7 @@ RUN pip install flashtext && \
     pip install vowpalwabbit && \
     pip install pydub && \
     pip install pydegensac && \
-    # b/215182966 torchmetrics 0.7.0 is causing an issue with pytorch-lightning.
-    pip install torchmetrics==0.6.2 && \
+    pip install torchmetrics && \
     pip install pytorch-lightning && \
     pip install datatable && \
     pip install sympy && \