fix: Always return a list of quantization bits values from get_quantization

[jeffkinnison]

ludwig.utils.config_utils.get_quantization returns the value of quantization.bits for LLM model types (either int or None type), but for ECD it returns a list of values to account for multiple LLM encoders. To simplify checking the quantization, get_quantization now returns a list in every case.

[github-actions]

Unit Test Results

  4 files  ±0    4 suites  ±0   9m 25s ⏱️ -17s
12 tests ±0    9 ✔️ ±0    3 💤 ±0  0 ❌ ±0 
40 runs  ±0  28 ✔️ ±0  12 💤 ±0  0 ❌ ±0 

Results for commit b958a34. ± Comparison against base commit 51f38c5.

♻️ This comment has been updated with latest results.