[SPARK-19421][ML][PYSPARK] Remove numClasses and numFeatures methods in LinearSVC

## What changes were proposed in this pull request?
Methods `numClasses` and `numFeatures` in LinearSVCModel are already usable by inheriting `JavaClassificationModel`
we should not explicitly add them.

## How was this patch tested?
existing tests

Author: Zheng RuiFeng <ruifengz@foxmail.com>

Closes #16727 from zhengruifeng/nits_in_linearSVC.

python/pyspark/ml/classification.py

@@ -172,22 +172,6 @@ class LinearSVCModel(JavaModel, JavaClassificationModel, JavaMLWritable, JavaMLR
         """
         return self._call_java("intercept")
 
-    @property
-    @since("2.2.0")
-    def numClasses(self):
-        """
-        Number of classes.
-        """
-        return self._call_java("numClasses")
-
-    @property
-    @since("2.2.0")
-    def numFeatures(self):
-        """
-        Number of features.
-        """
-        return self._call_java("numFeatures")
-
 
 @inherit_doc
 class LogisticRegression(JavaEstimator, HasFeaturesCol, HasLabelCol, HasPredictionCol, HasMaxIter,