[SPARK-26811][SQL][FOLLOWUP] some more document fixes

## What changes were proposed in this pull request?

while working on apache#24129, I realized that I missed some document fixes in apache#24285. This PR covers all of them.

## How was this patch tested?

N/A

Author: Wenchen Fan <wenchen@databricks.com>

Closes apache#24295 from cloud-fan/doc.

sql/core/src/main/java/org/apache/spark/sql/sources/v2/reader/Scan.java

@@ -62,7 +62,7 @@ default String description() {
   /**
    * Returns the physical representation of this scan for batch query. By default this method throws
    * exception, data sources must overwrite this method to provide an implementation, if the
-   * {@link Table} that creates this scan returns {@link TableCapability#BATCH_READ} in its
+   * {@link Table} that creates this scan returns {@link TableCapability#BATCH_READ} support in its
    * {@link Table#capabilities()}.
    *
    * @throws UnsupportedOperationException

sql/core/src/main/java/org/apache/spark/sql/sources/v2/writer/WriteBuilder.java

@@ -19,6 +19,7 @@
 
 import org.apache.spark.annotation.Evolving;
 import org.apache.spark.sql.sources.v2.Table;
+import org.apache.spark.sql.sources.v2.TableCapability;
 import org.apache.spark.sql.sources.v2.writer.streaming.StreamingWrite;
 import org.apache.spark.sql.types.StructType;
 
@@ -57,8 +58,8 @@ default WriteBuilder withInputDataSchema(StructType schema) {
   /**
    * Returns a {@link BatchWrite} to write data to batch source. By default this method throws
    * exception, data sources must overwrite this method to provide an implementation, if the
-   * {@link Table} that creates this write returns BATCH_WRITE support in its
-   * {@link Table#capabilities()}.
+   * {@link Table} that creates this write returns {@link TableCapability#BATCH_WRITE} support in
+   * its {@link Table#capabilities()}.
    *
    * Note that, the returned {@link BatchWrite} can be null if the implementation supports SaveMode,
    * to indicate that no writing is needed. We can clean it up after removing