Fix errors (#11804)

### What problem does this PR solve?

1. typos
2. grammar errors.

### Type of change

- [x] Refactoring

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

rag/app/book.py

@@ -70,7 +70,7 @@ def chunk(filename, binary=None, from_page=0, to_page=100000,
     """
         Supported file formats are docx, pdf, txt.
         Since a book is long and not all the parts are useful, if it's a PDF,
-        please setup the page ranges for every book in order eliminate negative effects and save elapsed computing time.
+        please set up the page ranges for every book in order eliminate negative effects and save elapsed computing time.
     """
     parser_config = kwargs.get(
         "parser_config", {

rag/app/qa.py

@@ -313,7 +313,7 @@ def mdQuestionLevel(s):
 def chunk(filename, binary=None, from_page=0, to_page=100000, lang="Chinese", callback=None, **kwargs):
     """
         Excel and csv(txt) format files are supported.
-        If the file is in excel format, there should be 2 column question and answer without header.
+        If the file is in Excel format, there should be 2 column question and answer without header.
         And question column is ahead of answer column.
         And it's O.K if it has multiple sheets as long as the columns are rightly composed.
 

rag/app/tag.py

@@ -37,7 +37,7 @@ def beAdoc(d, q, a, eng, row_num=-1):
 def chunk(filename, binary=None, lang="Chinese", callback=None, **kwargs):
     """
         Excel and csv(txt) format files are supported.
-        If the file is in excel format, there should be 2 column content and tags without header.
+        If the file is in Excel format, there should be 2 column content and tags without header.
         And content column is ahead of tags column.
         And it's O.K if it has multiple sheets as long as the columns are rightly composed.