[chore] Simplify the OTEL setup (#4110)

# Description

This simplifies our OTEL setup by:

* Getting rid of some deprecated things.
* Using `autoexport` and letting things get configured by the `OTEL_` environment variables.
* Removing all the unnecessary config options.

## Checklist

Please put an x inside each checkbox to indicate that you've read and followed it: `[ ]` -> `[x]`

If this is a documentation change, only the first checkbox must be filled (you can delete the others if you want).

- [x] I/we have read the [GoToSocial contribution guidelines](https://codeberg.org/superseriousbusiness/gotosocial/src/branch/main/CONTRIBUTING.md).
- [x] I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
- [x] I/we have not leveraged AI to create the proposed changes.
- [x] I/we have performed a self-review of added code.
- [x] I/we have written code that is legible and maintainable by others.
- [ ] I/we have commented the added code, particularly in hard-to-understand areas.
- [x] I/we have made any necessary changes to documentation.
- [ ] I/we have added tests that cover new code.
- [x] I/we have run tests and they pass locally with the changes.
- [x] I/we have run `go fmt ./...` and `golangci-lint run`.

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4110
Reviewed-by: tobi <kipvandenbos@noreply.codeberg.org>
Co-authored-by: Daenney <daenney@noreply.codeberg.org>
Co-committed-by: Daenney <daenney@noreply.codeberg.org>

vendor/go.opentelemetry.io/otel/sdk/log/doc.go

@@ -0,0 +1,36 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+/*
+Package log provides the OpenTelemetry Logs SDK.
+
+See https://opentelemetry.io/docs/concepts/signals/logs/ for information
+about the concept of OpenTelemetry Logs and
+https://opentelemetry.io/docs/concepts/components/ for more information
+about OpenTelemetry SDKs.
+
+The entry point for the log package is [NewLoggerProvider].
+[LoggerProvider] is the object that all Bridge API calls use to create
+Loggers, and ultimately emit log records.
+Also, it is an object that should be used to
+control the life-cycle (start, flush, and shutdown) of the Logs SDK.
+
+A LoggerProvider needs to be configured to process the log records, this is
+done by configuring it with a [Processor] implementation using [WithProcessor].
+The log package provides the [BatchProcessor] and [SimpleProcessor]
+that are configured with an [Exporter] implementation which
+exports the log records to given destination. See
+[go.opentelemetry.io/otel/exporters] for exporters that can be used with these
+Processors.
+
+The data generated by a LoggerProvider needs to include information about its
+origin. A LoggerProvider needs to be configured with a Resource, by using
+[WithResource], to include this information. This Resource
+should be used to describe the unique runtime environment instrumented code
+is being run on. That way when multiple instances of the code are collected
+at a single endpoint their origin is decipherable.
+
+See [go.opentelemetry.io/otel/log] for more information about
+the OpenTelemetry Logs Bridge API.
+*/
+package log // import "go.opentelemetry.io/otel/sdk/log"