maint: Add project metadata for license and classifiers (#175)

## Which problem is this PR solving?
Adds additional project metadata to describe the associated license and
python classifiers. This makes it easier for consumers to audit the
dependency for usage and requirements.

- Closes #174 

## Short description of the changes
- Add license and classifiers and entries to pyproject.toml

## How to verify that this has the expected result
The new metadata is added to built packages and discoverable once
published, eg on pypi.org

pyproject.toml

@@ -5,6 +5,19 @@ description = "Honeycomb OpenTelemetry Distro for Python"
 authors = ["Honeycomb <support@honeycomb.io>"]
 readme = "README.md"
 packages = [{include = "honeycomb", from = "src" }]
+license = "Apache-2.0"
+classifiers = [
+    "Development Status :: 4 - Beta",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: Apache Software License",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.7",
+    "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Typing :: Typed",
+]
 
 [tool.poetry.dependencies]
 python = "^3.7, >= 3.7.2"