Fix a few capitalization typos (#7244)

* Fix capitalization typos in TensorFlow and PennyLane

* Fix Cirq capitalization

Author: mhucka

docs/build/ecosystem.md

@@ -23,7 +23,7 @@ The following document provides an ecosystem overview of various open-source too
 |[Stim](https://github.com/quantumlib/stim)|Google|A library for high-speed simulation of Clifford circuits and quantum error correction|
 |[TensorFlow Quantum](https://tensorflow.org/quantum)|Google|A library for developing new quantum machine learning algorithms|
 |[unitary](https://github.com/quantumlib/unitary)|Google|An API library providing common operations for adding quantum behaviors to games|
-|[Pennylane](https://pennylane.ai/)|Xanadu|A library for quantum machine learning with TensorFlow, PyTorch, or NumPy|
+|[PennyLane](https://pennylane.ai/)|Xanadu|A library for quantum machine learning with TensorFlow, PyTorch, or NumPy|
 
 ## Development tools
 

docs/citation.md

@@ -10,5 +10,5 @@ When using our projects, please cite them according to the following guide:
 | Qualtran | https://github.com/quantumlib/qualtran#how-to-cite-qualtran |
 | ReCirq | https://github.com/quantumlib/ReCirq#how-to-cite-recirq |
 | Stim | https://github.com/quantumlib/stim#how-cite-stim |
-| Tensorflow Quantum | https://github.com/tensorflow/quantum#references|
+| TensorFlow Quantum | https://github.com/tensorflow/quantum#references|
 | Tesseract Decoder | https://github.com/quantumlib/tesseract-decoder#citation|

docs/dev/style.md

@@ -78,7 +78,7 @@ as documentation, but also on internal code so that the mypy type checker can
 help catch coding errors.
 
 For documentation purposes in particular, type annotations should match the way
-classes and functions are accessed by cirq users, which is typically on the
+classes and functions are accessed by Cirq users, which is typically on the
 top-level `cirq` namespace (for example, users use `cirq.Sampler` even though
 the sampler class is defined in `cirq.work.sampler.Sampler`). Code in `cirq-core`
 typically cannot import and use `cirq.Sampler` directly because this could