[doc]Fix the output error of Batch Reading from the Fallback Branch example

[chenxinwei]

Documentation

Simply fixes the output error of Batch Reading from the Fallback Branch example.

[yuzelin]

scan.fallback-branch means if the partition exists in main branch, read from the main branch. Otherwise, read from the fallback branch. The 20240725 result shouldn't contains peach because paimon reader only read main branch for this partition.

[chenxinwei]

scan.fallback-branch means if the partition exists in main branch, read from the main branch. Otherwise, read from the fallback branch. The 20240725 result shouldn't contains peach because paimon reader only read main branch for this partition.

Got it. Thanks for your explanation.