Drop Python 3.9 support (#5076)

* Drop python 3.9 support

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* fix

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* fix exporter requirements.txt

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* do not skip  in pypy+windows

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* pin requirements

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* pin based on py version

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* revert argument name

* fix broken links in README.md

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* fix sdk configuration models

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* fix codegen and opentelemetry-proto-json

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* add changelo

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* remove helper script to fix typealias for datamodel-codegen

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* revert proto-json version

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

* Apply suggestion from @emdneto

* Apply suggestion from @xrmx

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Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>
Co-authored-by: Riccardo Magliocchetti <riccardo.magliocchetti@gmail.com>