Mark next release as 1.7 instead of 2.0 (#8281)

python-package/xgboost/VERSION

@@ -1 +1 @@
-2.0.0-dev
+1.7.0-dev

python-package/xgboost/core.py

@@ -1249,7 +1249,7 @@ class QuantileDMatrix(DMatrix):
         reference (the training dataset) ``QuantileDMatrix`` using ``ref`` as some
         information may be lost in quantisation.
 
-    .. versionadded:: 2.0.0
+    .. versionadded:: 1.7.0
 
     Parameters
     ----------
@@ -1373,7 +1373,7 @@ class QuantileDMatrix(DMatrix):
 class DeviceQuantileDMatrix(QuantileDMatrix):
     """ Use `QuantileDMatrix` instead.
 
-    .. deprecated:: 2.0.0
+    .. deprecated:: 1.7.0
 
     .. versionadded:: 1.1.0
 

python-package/xgboost/dask.py

@@ -695,7 +695,7 @@ class DaskQuantileDMatrix(DaskDMatrix):
 class DaskDeviceQuantileDMatrix(DaskQuantileDMatrix):
     """Use `DaskQuantileDMatrix` instead.
 
-    .. deprecated:: 2.0.0
+    .. deprecated:: 1.7.0
 
     .. versionadded:: 1.2.0
 

python-package/xgboost/sklearn.py

@@ -235,7 +235,7 @@ __model_doc = f"""
 
     feature_types : FeatureTypes
 
-        .. versionadded:: 2.0.0
+        .. versionadded:: 1.7.0
 
         Used for specifying feature types without constructing a dataframe. See
         :py:class:`DMatrix` for details.
@@ -1402,9 +1402,9 @@ class XGBClassifier(XGBModel, XGBClassifierBase):
         # must match the parameters for `get_params`
         self.use_label_encoder = use_label_encoder
         if use_label_encoder is True:
-            raise ValueError("Label encoder was removed in 1.6.")
+            raise ValueError("Label encoder was removed in 1.6.0.")
         if use_label_encoder is not None:
-            warnings.warn("`use_label_encoder` is deprecated in 2.0.0.")
+            warnings.warn("`use_label_encoder` is deprecated in 1.7.0.")
         super().__init__(objective=objective, **kwargs)
 
     @_deprecate_positional_args