Fixed some minor gramatical issues (#11530)

* Fixed some gramatical mistakes (#82)

* Update discover_llamaindex.md

* Update installation.md

* Update reading.md

* Update starter_example.md

* Update starter_example_local.md

* Update v0_10_0_migration.md

* Update 2024-02-28-rag-bootcamp-vector-institute.ipynb

* Update multimodal.md

* Update chatbots.md