## What changes were proposed in this pull request?
This PR proposes to add cmd scripts so that Windows users can also run `spark-sql` script.
## How was this patch tested?
Manually tested on Windows.
**Before**
```cmd
C:\...\spark>.\bin\spark-sql
'.\bin\spark-sql' is not recognized as an internal or external command,
operable program or batch file.
C:\...\spark>.\bin\spark-sql.cmd
'.\bin\spark-sql.cmd' is not recognized as an internal or external command,
operable program or batch file.
```
**After**
```cmd
C:\...\spark>.\bin\spark-sql
...
spark-sql> SELECT 'Hello World !!';
...
Hello World !!
```
Author: hyukjinkwon <gurwls223@gmail.com>
Closes#19808 from HyukjinKwon/spark-sql-cmd.
## What changes were proposed in this pull request?
Fixing the way how `SPARK_HOME` is resolved on Windows. While the previous version was working with the built release download, the set of directories changed slightly for the PySpark `pip` or `conda` install. This has been reflected in Linux files in `bin` but not for Windows `cmd` files.
First fix improves the way how the `jars` directory is found, as this was stoping Windows version of `pip/conda` install from working; JARs were not found by on Session/Context setup.
Second fix is adding `find-spark-home.cmd` script, which uses `find_spark_home.py` script, as the Linux version, to resolve `SPARK_HOME`. It is based on `find-spark-home` bash script, though, some operations are done in different order due to the `cmd` script language limitations. If environment variable is set, the Python script `find_spark_home.py` will not be run. The process can fail if Python is not installed, but it will mostly use this way if PySpark is installed via `pip/conda`, thus, there is some Python in the system.
## How was this patch tested?
Tested on local installation.
Author: Jakub Nowacki <j.s.nowacki@gmail.com>
Closes#19370 from jsnowacki/fix_spark_cmds.
