gh-36373: Enable conda ci for all PRs and remove experimental label
    
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Using conda to install all sage dependencies is pretty stable and has
been long enough in "experimental mode". We remove here the experimental
flag and in order to make sure that the workflow is not breaking enable
the conda-ci on all PRs. This also provides a) faster feedback as the
whole build+test takes only about 1.5h (which is less time then what
only the "incremental build" currently takes) and b) tests that the code
is working on all supported python versions. The last remaining failing
tests under linux are temporarily disabled in
#36372.

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URL: #36373
Reported by: Tobias Diez
Reviewer(s): Matthias Köppe

Author: Release Manager

.github/workflows/ci-conda.yml

@@ -7,13 +7,6 @@ on:
     branches:
       - 'public/build/**-runci'
   pull_request:
-    types:
-      # Defaults
-      - opened
-      - synchronize
-      - reopened
-      # When a CI label is added
-      - labeled
   workflow_dispatch:
     # Allow to run manually
 
@@ -27,20 +20,9 @@ jobs:
     name: Conda
     runs-on: ${{ matrix.os }}
 
-    # Run on push, workflow dispatch and when certain labels are added or are present
-    if: |
-      github.event_name != 'pull_request' ||
-      ((github.event.action != 'labeled' &&
-         (contains(github.event.pull_request.labels.*.name, 'c: packages: standard') ||
-          contains(github.event.pull_request.labels.*.name, 'c: packages: optional') ||
-          contains(github.event.pull_request.labels.*.name, 's: run conda ci'))) ||
-       (github.event.action == 'labeled' &&
-         (github.event.label.name == 'c: packages: optional' ||
-          github.event.label.name == 'c: packages: standard' ||
-          github.event.label.name == 's: run conda ci')))
-
     strategy:
-      fail-fast: false
+      fail-fast: ${{ github.event_name == 'pull_request' }}
+      max-parallel: ${{ github.event_name == 'pull_request' && 2 || 6 }}
       matrix:
         os: [ubuntu-latest, macos-latest]
         python: ['3.9', '3.10', '3.11']

src/doc/en/installation/conda.rst

@@ -93,17 +93,14 @@ from source as follows:
 
 .. _sec-installation-conda-develop:
 
-Using conda to provide all dependencies for the Sage library (experimental)
+Using conda to provide all dependencies for the Sage library
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 You can build and install the Sage library from source, using conda to
 provide all of its dependencies. This bypasses most of the build
 system of the Sage distribution and is the fastest way to set up an
 environment for Sage development.
 
-Note that this is still an experimental feature and may not work as
-intended.
-
 Here we assume that you are using a git checkout.
 
   - Optionally, set the build parallelism for the Sage library. Use