ARROW-7565: [Website] Add support for download URL redirect (#40)

diff --git a/install.md b/install.md
index 6ed056f..ca8e979 100644
--- a/install.md
+++ b/install.md
@@ -106,7 +106,7 @@
 ```shell
 sudo apt update
 sudo apt install -y -V apt-transport-https curl gnupg lsb-release
-sudo curl --output /usr/share/keyrings/apache-arrow-keyring.gpg https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/apache-arrow-keyring.gpg
+sudo curl -L --output /usr/share/keyrings/apache-arrow-keyring.gpg https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/apache-arrow-keyring.gpg
 sudo tee /etc/apt/sources.list.d/apache-arrow.list <<APT_LINE
 deb [arch=amd64 signed-by=/usr/share/keyrings/apache-arrow-keyring.gpg] https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/ $(lsb_release --codename --short) main
 deb-src [signed-by=/usr/share/keyrings/apache-arrow-keyring.gpg] https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/ $(lsb_release --codename --short) main
@@ -131,7 +131,7 @@
 sudo tee /etc/apt/sources.list.d/backports.list <<APT_LINE
 deb http://deb.debian.org/debian $(lsb_release --codename --short)-backports main
 APT_LINE
-sudo curl --output /usr/share/keyrings/apache-arrow-keyring.gpg https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/apache-arrow-keyring.gpg
+sudo curl -L --output /usr/share/keyrings/apache-arrow-keyring.gpg https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/apache-arrow-keyring.gpg
 sudo tee /etc/apt/sources.list.d/apache-arrow.list <<APT_LINE
 deb [arch=amd64 signed-by=/usr/share/keyrings/apache-arrow-keyring.gpg] https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/ $(lsb_release --codename --short) main
 deb-src [signed-by=/usr/share/keyrings/apache-arrow-keyring.gpg] https://dl.bintray.com/apache/arrow/$(lsb_release --id --short | tr 'A-Z' 'a-z')/ $(lsb_release --codename --short) main