Encoder crash for OSBA ISM3SBA1 at 13.2 and 16.4 kbps in gauss_L2_ivas_fx()
# Basic info
<!--- Add commit SHA used to reproduce -->
- Float reference:
- Encoder (float):
- Decoder (float):
- Fixed point:
- Encoder (fixed): ca5e99f0cd9c482406736e68952a1f91b69f62f7
- Decoder (fixed):
# Bug description
The fixed point encoder crashes with an assert:
```
Assertion failed: (0), function L_add, file basop32.c, line 1784.
```



# Ways to reproduce
Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-1167
<!-- Commandline or script -->
```bash
./IVAS_cod_fx -ism_sba 3 1 ISM3SBA1_3_female_noOverlap.0.csv ISM3SBA1_3_female_noOverlap.1.csv ISM3SBA1_3_female_noOverlap.2.csv -max_band WB 13200 16 ISM3SBA1_3_female_noOverlap_16.wav
./IVAS_cod_fx -ism_sba 3 1 ISM3SBA1_3_female_noOverlap.0.csv ISM3SBA1_3_female_noOverlap.1.csv ISM3SBA1_3_female_noOverlap.2.csv -max_band WB 16400 16 ISM3SBA1_3_female_noOverlap_16.wav
```
This crash also occurs for both bitrate at sampling rates of 32kHz and 48kHz with ±10dB gain on the input file. All input versions have been uploaded, metadata files remain the same regardless of input file.
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issue