docs: seperate build_docs html and pdf CI jobs

Due to eager_exclude, Sphinx jobs cannot use the doc cache (doctrees).

PDF and HTML building are now seperate CI jobs to avoid this issue.
PDF building will only be ran on deploy branches and when started
with build_docs tag to reduce CI load

tools/ci/config/build.yml

@@ -231,7 +231,6 @@ build_component_ut_esp32s2:
     paths:
       - docs/_build/*/*/*.txt
       - docs/_build/*/*/html/*
-      - docs/_build/*/*/latex/*
     expire_in: 4 days
   only:
     variables:
@@ -243,31 +242,39 @@ build_component_ut_esp32s2:
   script:
     - cd docs
     - ${IDF_PATH}/tools/ci/multirun_with_pyenv.sh -p 3.6.10 pip install -r requirements.txt
-    - ${IDF_PATH}/tools/ci/multirun_with_pyenv.sh -p 3.6.10 ./build_docs.py -bs html latex -l $DOCLANG -t $DOCTGT build
+    - ${IDF_PATH}/tools/ci/multirun_with_pyenv.sh -p 3.6.10 ./build_docs.py -bs html -l $DOCLANG -t $DOCTGT build
 
-build_docs_en_esp32:
+build_docs_html:
   extends: .build_docs_template
-  variables:
-    DOCLANG: "en"
-    DOCTGT: "esp32"
+  parallel:
+    matrix:
+      - DOCLANG: ["en", "zh_CN"]
+        DOCTGT: ["esp32", "esp32s2"]
 
-build_docs_en_esp32s2:
-  extends: .build_docs_template
-  variables:
-    DOCLANG: "en"
-    DOCTGT: "esp32s2"
-
-build_docs_zh_CN_esp32:
-  extends: .build_docs_template
-  variables:
-    DOCLANG: "zh_CN"
-    DOCTGT: "esp32"
-
-build_docs_zh_CN_esp32s2:
-  extends: .build_docs_template
-  variables:
-    DOCLANG: "zh_CN"
-    DOCTGT: "esp32s2"
+build_docs_pdf:
+  stage: build
+  image: $ESP_IDF_DOC_ENV_IMAGE
+  tags:
+    - build_docs
+  artifacts:
+    when: always
+    paths:
+      - docs/_build/*/*/latex/*
+    expire_in: 4 days
+  rules:
+    - if: '$CI_COMMIT_REF_NAME == "master"'
+    - if: '$CI_COMMIT_REF_NAME =~ "/^release\/v/"'
+    - if: '$CI_COMMIT_REF_NAME =~ "/^v\d+\.\d+(\.\d+)?($|-)/"'
+    - if: $BOT_LABEL_BUILD_DOCS
+  dependencies: []
+  parallel:
+    matrix:
+      - DOCLANG: ["en", "zh_CN"]
+        DOCTGT: ["esp32", "esp32s2"]
+  script:
+    - cd docs
+    - ${IDF_PATH}/tools/ci/multirun_with_pyenv.sh -p 3.6.10 pip install -r requirements.txt
+    - ${IDF_PATH}/tools/ci/multirun_with_pyenv.sh -p 3.6.10 ./build_docs.py -bs latex -l $DOCLANG -t $DOCTGT build
 
 test_build_system:
   extends: .build_template

tools/ci/config/deploy.yml

@@ -82,10 +82,8 @@ push_to_github:
     - deploy
     - shiny
   dependencies:
-    - build_docs_en_esp32
-    - build_docs_en_esp32s2
-    - build_docs_zh_CN_esp32
-    - build_docs_zh_CN_esp32s2
+    - build_docs_html
+    - build_docs_pdf
   variables:
     DOCS_BUILD_DIR: "${IDF_PATH}/docs/_build/"
     PYTHONUNBUFFERED: 1