[MINOR][DOCS] Replace non-breaking space to normal spaces that breaks rendering markdown

[HyukjinKwon]

What changes were proposed in this pull request?

It seems there are several non-breaking spaces were inserted into several .mds and they look breaking rendering markdown files.

These are different. For example, this can be checked via python as below:

>>> " "
'\xc2\xa0'
>>> " "
' '

Note that it seems this PR description automatically replaces non-breaking spaces into normal spaces. Please open a vi and copy and paste it into python to verify this (do not copy the characters here).

I checked the output below in Sapari and Chrome on Mac OS and, Internal Explorer on Windows 10.

Before

After

How was this patch tested?

Manually checking.

These instances were found via

grep --include=*.scala --include=*.python --include=*.java --include=*.r --include=*.R --include=*.md --include=*.r -r -I " " .

in Mac OS.

It seems there are several instances more as below:

./docs/sql-programming-guide.md:        │   ├── ...
./docs/sql-programming-guide.md:        │   │
./docs/sql-programming-guide.md:        │   ├── country=US
./docs/sql-programming-guide.md:        │   │   └── data.parquet
./docs/sql-programming-guide.md:        │   ├── country=CN
./docs/sql-programming-guide.md:        │   │   └── data.parquet
./docs/sql-programming-guide.md:        │   └── ...
./docs/sql-programming-guide.md:            ├── ...
./docs/sql-programming-guide.md:            │
./docs/sql-programming-guide.md:            ├── country=US
./docs/sql-programming-guide.md:            │   └── data.parquet
./docs/sql-programming-guide.md:            ├── country=CN
./docs/sql-programming-guide.md:            │   └── data.parquet
./docs/sql-programming-guide.md:            └── ...
./sql/core/src/test/README.md:│   ├── *.avdl                  # Testing Avro IDL(s)
./sql/core/src/test/README.md:│   └── *.avpr                  # !! NO TOUCH !! Protocol files generated from Avro IDL(s)
./sql/core/src/test/README.md:│   ├── gen-avro.sh             # Script used to generate Java code for Avro
./sql/core/src/test/README.md:│   └── gen-thrift.sh           # Script used to generate Java code for Thrift

These seems generated via tree command which inserts non-breaking spaces. They do not look causing any problem for rendering within code blocks and I did not fix it to reduce the overhead to manually replace it when it is overwritten via tree command in the future.

[HyukjinKwon]

These seems mistakenly added. So, I decided to fix it here.

[HyukjinKwon]

Open a vi and copy it and print it within python to verify this.

>>> "`[app-id]` will actually be `[base-app-id]/[attempt-id]`, where `[base-app-id]` is the YARN application ID"
'`[app-id]`\xc2\xa0will actually be\xc2\xa0`[base-app-id]/[attempt-id]`, where `[base-app-id]`\xc2\xa0is the YARN application ID'

[HyukjinKwon]

cc @srowen. Could you take a look please?

[HyukjinKwon]

>>> "## Encrypted Filesystems"
'##\xc2\xa0Encrypted Filesystems'

[HyukjinKwon]

>>> "## Contributing"
'##\xc2\xa0Contributing'

[SparkQA]

Test build #75471 has finished for PR 17517 at commit 4b0e56a.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[srowen]

Merged to master/2.1