doc/main: Drop beta tag.

Less variants is better. Now we'll just have to add beta support for SPIKE in the next release.

Fixes #102

doc/Makefile

@@ -8,13 +8,10 @@ SPHINXPROJ    = Pybricks
 SOURCEDIR     = main
 BUILDDIR      = "$(SOURCEDIR)"/build
 TAG           = main
-ifeq ($(BETA),1)
-	BETATAG   = "-tbeta"
-endif
 
 # Put it first so that "make" without argument is like "make help".
 help:
-	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(TAG) $(BETATAG) $(O)
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(TAG) $(O)
 
 .PHONY: help Makefile
 
@@ -25,4 +22,4 @@ diagrams:
 # Catch-all target: route all unknown targets to Sphinx using the new
 # "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
 %: Makefile
-	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) -t $(TAG) $(BETATAG) $(O)
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) -t $(TAG) $(O)

doc/main/conf.py

@@ -25,10 +25,6 @@
 if os.environ.get("READTHEDOCS", None) == "True":
     tags.add("main")  # noqa F821
 
-# On https://docs.pybricks.com/en/latest/, show features tagged as beta.
-if os.environ.get("READTHEDOCS_VERSION_NAME", None) == "latest":
-    tags.add("beta")  # noqa F821
-
 # Addtional configuration of the IDE docs
 if "ide" in tags.tags:  # noqa F821
     _DISCLAIMER = ""