Invalid indentation level due to too long of regex

## Bug Report

**Describe the bug**
When using a custom regex parser with a very long Regex, I receive the error `Invalid indentation level` when running Fluent Bit. This appears to be similar to issue #301 where the line buffer is not long enough.

**To Reproduce**
Create a parser with a very long Regex. I am using one that is currently 4,365 characters.

```
[PARSER]
Name test_parser
Format regex
Regex <
```

Consume said parser with a parser filter.

```
[FILTER]
Name parser
Match *
Key_Name log
Parser test_parser
```

Start Fluent Bit and you'll receive the error `Invalid indentation level`. Fluent Bit will also fail to start.

**Expected behavior**
I expect Fluent Bit to start without error or quitting and for my logs to be properly parsed.

**Screenshots**
N/A

**Your Environment**
* Version used: 1.0.4 (Docker version)
* Operating System and version: MacOS running containerized Fluent Bit
* Filters and plugins: Parser and Parser Filter

**Additional context**
We are parsing some complicated log for OpenLDAP and thus need a pretty gnarly regex to be able to parse and extract all of the fields.