fix: replace \u0002, \u0003 in common text

[drunkpig]

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5.pdf

Motivation

some digital pdf will produce \u002, \u003 in markdown result. This cause by pymupdf , wen just replace these special chars.
\u0000 (NUL): Null character
\u0001 (SOH): Start of Header
\u0002 (STX): Start of Text
\u0003 (ETX): End of Text
\u0004 (EOT): End of Transmission
\u0005 (ENQ): Enquiry
\u0006 (ACK): Acknowledge
\u0007 (BEL): Bell (causes an alert sound)
\u0008 (BS): Backspace
\u0009 (HT): Horizontal Tab
\u000A (LF): Line Feed (New Line)
\u000B (VT): Vertical Tab
\u000C (FF): Form Feed
\u000D (CR): Carriage Return
\u000E (SO): Shift Out
\u000F (SI): Shift In

Modification

Please briefly describe what modification is made in this PR.

BC-breaking (Optional)

Does the modification introduce changes that break the backward compatibility of the downstream repositories?
If so, please describe how it breaks the compatibility and how the downstream projects should modify their code to keep compatibility with this PR.

Use cases (Optional)

If this PR introduces a new feature, it is better to list some use cases here and update the documentation.

Checklist

Before PR:

• [ x] Pre-commit or other linting tools are used to fix the potential lint issues.
• [x ] Bug fixes are fully covered by unit tests, the case that causes the bug should be added in the unit tests.
• [x ] The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
• [ x] The documentation has been modified accordingly, like docstring or example tutorials.

After PR:

• [x ] If the modification has potential influence on downstream or other related projects, this PR should be tested with those projects.
• [ x] CLA has been sign

ed and all committers have signed the CLA in this PR.