ci+docs: support CentOS Stream 9, drop CentOS 8

Refs: #5181
Change-Id: I1d1a0ed02736ef5ec0c28d51f1c4f56f6e00d129
diff --git a/.jenkins.d/00-deps.sh b/.jenkins.d/00-deps.sh
index fb63468..d3b16f9 100755
--- a/.jenkins.d/00-deps.sh
+++ b/.jenkins.d/00-deps.sh
@@ -43,7 +43,7 @@
             ;;
     esac
 
-elif has CentOS-8 $NODE_LABELS; then
+elif has CentOS $NODE_LABELS; then
     sudo dnf -y install gcc-c++ libasan pkgconf-pkg-config python3 \
                         boost-devel openssl-devel sqlite-devel
 fi
diff --git a/.jenkins.d/10-build.sh b/.jenkins.d/10-build.sh
index f2ddf0c..a4e6cd5 100755
--- a/.jenkins.d/10-build.sh
+++ b/.jenkins.d/10-build.sh
@@ -10,8 +10,7 @@
 if [[ $JOB_NAME == *"code-coverage" ]]; then
     COVERAGE="--with-coverage"
 fi
-if has CentOS-8 $NODE_LABELS; then
-    # https://bugzilla.redhat.com/show_bug.cgi?id=1721553
+if [[ -n $DISABLE_PCH ]]; then
     PCH="--without-pch"
 fi
 
@@ -40,7 +39,7 @@
 # Install
 sudo_preserve_env PATH -- ./waf --color=yes install
 
-if has CentOS-8 $NODE_LABELS; then
+if has CentOS $NODE_LABELS; then
     sudo tee /etc/ld.so.conf.d/ndn.conf >/dev/null <<< /usr/local/lib64
 fi
 if has Linux $NODE_LABELS; then
diff --git a/.jenkins.d/20-tests.sh b/.jenkins.d/20-tests.sh
index a752c72..d34fd88 100755
--- a/.jenkins.d/20-tests.sh
+++ b/.jenkins.d/20-tests.sh
@@ -8,8 +8,6 @@
     security unlock-keychain -p named-data
 fi
 
-ndnsec key-gen "/tmp/jenkins/$NODE_NAME" | ndnsec cert-install -
-
 # https://github.com/google/sanitizers/wiki/AddressSanitizerFlags
 ASAN_OPTIONS="color=always"
 ASAN_OPTIONS+=":check_initialization_order=1"
diff --git a/.jenkins.d/40-headers-check.sh b/.jenkins.d/40-headers-check.sh
index 861d8c9..e3493f4 100755
--- a/.jenkins.d/40-headers-check.sh
+++ b/.jenkins.d/40-headers-check.sh
@@ -13,7 +13,7 @@
   exit 0
 fi
 
-if has CentOS-8 $NODE_LABELS; then
+if has CentOS $NODE_LABELS; then
   export PKG_CONFIG_PATH=/usr/local/lib64/pkgconfig
 fi
 
diff --git a/docs/INSTALL.rst b/docs/INSTALL.rst
index 25438da..0393475 100644
--- a/docs/INSTALL.rst
+++ b/docs/INSTALL.rst
@@ -10,9 +10,9 @@
 -  Ubuntu 18.04 (amd64, armhf, i386)
 -  Ubuntu 20.04 (amd64)
 -  Ubuntu 21.10 (amd64)
+-  CentOS Stream 9
 -  macOS 10.15
 -  macOS 11 (Intel only)
--  CentOS 8
 
 ndn-cxx is known to work on the following platforms, although they are not officially
 supported:
@@ -109,7 +109,6 @@
 
   .. code-block:: sh
 
-    sudo dnf config-manager --enable powertools  # on CentOS only
     sudo dnf install doxygen graphviz python3-pip
     pip3 install --user sphinx sphinxcontrib-doxylink
 
@@ -137,7 +136,7 @@
 
 .. code-block:: sh
 
-    ./waf configure  # on CentOS, add --without-pch
+    ./waf configure
     ./waf
     sudo ./waf install
 
@@ -164,12 +163,12 @@
     sudo ldconfig
 
 .. note::
-  When the library is installed in a non-standard path (in general: not in ``/usr/lib``
-  or ``/usr/local/lib``; on some Linux distros including Fedora: not in ``/usr/lib``),
-  additional actions may be necessary.
+  When the library is installed in a non-default location (in general: not in ``/usr/lib``
+  or ``/usr/local/lib``; on some Linux distros like Fedora and its derivatives, including
+  CentOS: not in ``/usr/lib``), the following additional actions may be necessary.
 
-  The installation path should be added to ``/etc/ld.so.conf`` (or in
-  ``/etc/ld.so.conf.d``) **before** running ``sudo ldconfig``. For example:
+  The library installation path should be added to ``/etc/ld.so.conf`` or in
+  ``/etc/ld.so.conf.d/*.conf`` **before** running ``ldconfig``. For example:
 
   .. code-block:: sh
 
@@ -215,7 +214,7 @@
 
 .. code-block:: sh
 
-    ./waf configure --with-examples  # on CentOS, add --without-pch
+    ./waf configure --with-examples
     ./waf
     sudo ./waf install
     sudo ldconfig  # on Linux only
@@ -306,7 +305,7 @@
 
 .. code-block:: sh
 
-    ./waf configure --debug --with-tests  # on CentOS, add --without-pch
+    ./waf configure --debug --with-tests
     ./waf
     sudo ./waf install
     sudo ldconfig  # on Linux only