According to Reuters, the goal of the Israeli strikes is to disrupt arms delivery to Iran's allies in Syria and Lebanon:
Regional and intelligence sources say Israel has in recent months
intensified strikes on Syrian airports and air bases to disrupt Iran's
increasing use of aerial supply lines to deliver arms to allies in
Syria and Lebanon including Lebanon's Iran-backed Hezbollah.
Aljazeera provides more geopolitical context mentioning that the strikes are also a warning to both Iran and Syria:
“The attack is a warning to Iran insofar that it seeks to
demonstrate that Tel Aviv will continue to resist the imposition of
the new political dynamics of the nuclear deal in spite of
Washington,” Hamdi told Al Jazeera.
It is also “a warning to al-Assad that there will be consequences to
Syria’s infrastructure if it is used to facilitate the anticipated
entrenchment of Iran’s reach that the nuclear deal is expected to
bring about”, he continued.
France24 briefly mentions the rationale of the strikes from Israel's perspective:
Israel has repeatedly bombed Iran-backed militia targets in Syria in
recent years, saying its goal is to erode Tehran's military presence,
which Western intelligence sources say has expanded in the war-torn
country.
They say Iran has a strong presence in the Sayeda Zainab neighbourhood
of southern Damascus, where militias that it backs have underground
bases.
As a side note, these strikes are not new and they target military positions:
Israel has bombed Syrian airports and military positions numerous
times over the course of the 11-year war in Syria.